Yeah, those are the best places Online for primary material. Best place in the real world would be the city archives, on the top floor of the Library of Birmingham. They have a huge map collection.
I am fairly sure on investigating the map room, shorty after the opening of the new library, I actually found a map with these old constituencies on, something I was interested in, as I hadn't been able to make any sense of the changes in Birmingham just from electorates and present day maps, which is usually good enough.
Eye Rye Hythe Hyde South Molton Eton and Slough Isle of Thanet Isle of Ely Clay Cross Holland with Boston Ince The Hartlepools Houghton-le-Spring Barnard Castle Buckrose Barkston Ash Ross and Cromarty Biggleswade Cockermouth St Augustine's Osgoldcross East Looe St Germans Plympton Erle Beeralston Great Marlow Weobley
That (with a bit of rearrangement) gives me an idea for a poem
Labour governments are always voted in by empty minds, and voted out by empty pockets