Three questions, hope you dont mind Bertram born in 1898 and his brother Sidney

[Ray T]

Is it the whole thing that's A3 (including the mount) or just the photo? If the former you might just get the two figures on an A4 scan.

Failing that, you could try photographing it. You need to make sure the photograph is exactly parallel to the camera and you should bracket your exposures; i.e. take several photographs under-exposing and over-exposing which you think is the correct one.

Your biggest problem will be lighting - try doing it outside on a cloudy day; preferably after the snow has melted!

[Gadget]

Unless you are an expert photgrapher, do not, repeat, do not attempt to do what Ray has said. You need to have perfect lighting and specialist equipment to ensure that you have the photo and lens parallel. 

In addition to specialist photographers, many Libraries and Museums  have these facilities and often will take a photograph for a small fee.


Gadget

[Karen McDonald]

I'd prefer to think that he did indeed have 2 legs, but I'm not convinced... 

I can't see that his leg is pointing backwards. The lower edge of the chair is too visible.
 
I can't see a foot resting on his thigh. There is a smear across the photo (or glass) which crosses that area.
Also, why would he sit like that? The photo is very prim & proper, the boys are in their best clothes. The younger boy is almost standing to attention! That his brother would sit with one leg up on the other is a bit weird.

I may not be a spring chicken but I'm still fairly supple  but when I try and sit with my right foot up on my left thigh and then rest my left arm on it, my hand is much higher than his is in the photo. If his right foot is on his left thigh, his hand would need to be higher, I think. It looks as though his left arm is simply resting on his left thigh.

Just my two penn'th...

[Sinann]

I'd prefer to think that he did indeed have 2 legs, but I'm not convinced... 

I can't see that his leg is pointing backwards. The lower edge of the chair is too visible.
 
I can't see a foot resting on his thigh. There is a smear across the photo (or glass) which crosses that area.
Also, why would he sit like that? The photo is very prim & proper, the boys are in their best clothes. The younger boy is almost standing to attention! That his brother would sit with one leg up on the other is a bit weird.

I may not be a spring chicken but I'm still fairly supple  but when I try and sit with my right foot up on my left thigh and then rest my left arm on it, my hand is much higher than his is in the photo. If his right foot is on his left thigh, his hand would need to be higher, I think. It looks as though his left arm is simply resting on his left thigh.

Just my two penn'th...

My thoughts exactly. I can't see how the level of both knees would match in such a position.

[Ray T]

Unless you are an expert photgrapher, do not, repeat, do not attempt to do what Ray has said. You need to have perfect lighting and specialist equipment to ensure that you have the photo and lens parallel. 

I can't think for the life of me what damage could be done by using a DiY approach. I wouldn't call myself an expert photographer, by any means, but I have, in past times, been accepted for international exhibitions and successfully duplicated slides using two pieces of drain-pipe, some off-cuts of cardboard and a few inches of gaffer tape. Heaven forbid that someone might try something for themselves and actually learn something!

[Gadget]

Not damage - just that without proper equipment it's very very difficult and much easier to let someone who knows do it.

I also have exhibited and had prizes for photography - I studied it to postgrad level and have taught it,

Don't be so aggressive.

[Ray T]

Not damage - just that without proper equipment it's very very difficult and much easier to let someone who knows do it.

I also have exhibited and had prizes for photography - I studied it to postgrad level and have taught it,

Don't be so aggressive.

So "do not, repeat do not attempt to do" isn't being aggressive?

If you have studied to post-grad level and taught it you will appreciate that today's average mobile 'phone can take more precise and accurate photographs than the equipment used to photograph the original image.

Matter closed.

[Gadget]

It's the parallel that's the problem not the camera. You need to have the camera exactly parrallel to the original. That's why they use a special stand in libraries and museums. Otherwise there is distortion.

[Ray T]

........ and there was no distortion whatsoever in cameras made in the early 20C, and there is no such thing as depth of field, and there's no chance whatsoever of a pure amateur getting acceptable results, and distortion can't be corrected on the computer, and if we hadn't had such a thing as trial and error, photography would never have been invented in the first place.

What the o/p wants is a half decent and cheap copy of the photograph, not forensic exhibit.

As I said, matter closed.