I haven'tlogged in here for quite a while, so I've just had a fresh look at this.
ShaunJ said Galeries Lafayette was in the phone books from about 1927-1966 at 190 Regent St, and this 1928 newspaper ad for Galeries Lafayette states 188/196 Regent Street (
https://www.flickr.com/photos/bradford_timeline/20690549191 ). So the Galeries Lafayette seem to have been at the same address (around 190, plus a few numbers either side) for that whole period.
Current address of Hamleys (
http://www.hamleys.com/explore-stores.irs ) is 188-196 Regent Street. Unless street numbering changed that's exactly where Galeries Lafayette was in the 1928 ad.
I just found a few photos of Regent Street in 1952 at WestminsterMemories.org.uk:
200-206 (
http://www.westminstermemories.org.uk/page_id__10_img__40.aspx):
- Jaeger House
- Hamleys (so in 1952 Hamleys was in a slightly different place, a few shops north of it's current location)
188-198 unfortunately no photo, although Galeries Lafayette should be here.
176-186 (
http://www.westminstermemories.org.uk/page_id__10_img__39.aspx ):
- Kodak
- Boots
- Richard Shops
- Ciao(?) Pearls
- Imperial Fur Store
I also (thanks to Anita9659) found the Galeries Lafayette bit in an Indian cut of the 1970 movie "Cool It Carol" (one of those awful Robin Askwith movies!) on Youtube. Around the point that Anita mentioned there's a shot up the street from Galeries Lafayette, but I can't make out the shop names (nothing that immediately strikes me as being Hamleys). And then when she walks south from Galeries Lafayette the next shop is definitely a Kodak shop (assuming no jump cuts), and the next could be Boots?
So it seems fairly likely that Hamleys (guessing 200-202) and Galeries Lafayette (188-196) were actually neighbours (maybe with something else in between at 198?) for the whole of the 1960's, and after Galeries Lafayette closed Hamleys moved a few shops south and took over the Galeries Lafayette premises.
I think this would mean that everybody's correct to some extent !