Thanks once again for all the replies everyone!
In terms of age, my grandmother did always look a little older than she was; she'd had ten children after all! She was only in her sixties when she died in the late 90s.
The other woman that Ohbodder identified did catch the eye of my mum and I as a potential relative. We think it's possible that it may be my grandmother's sister, Ivy. We can't easily tell though, as we have no photos of her.
Ivy was about eight years the elder, being born in 1921. Her married name was Garratt, and her husband's name was Horace John Garratt. Ivy died in 2004 and is buried in Neenton cemetery near Bridgnorth, Shropshire. Throwing the above out there into the aether just in case someone knows of her and might have a picture for comparison!
Interestingly, as a child my mum remembers her mother wearing her hair in a very similar way to the woman on the left. Worn long, brushed down forward and then rolled back up into position around the head. She only adopted the perm hairstyle in her later years.
