That's two forumites I've met in one evening!
In case anyone else is wondering, the answer is yes. The springs don't have the same ends as the originals but they are long enough and do fit.Is it the same spring across all dual height workmates?
Black & Decker Workmate Spring 797516
Black & Decker WM626 Type 1 Workmate Spare Parts | Miles Tool & Machinery Centre
An exploded drawing and spare parts listing for the Black & Decker WM626 Type 1 Workmatewww.mtmc.co.ukBlack & Decker Workmate Spring 797516 - Part Shop Direct
Black & Decker Workmate Spring 797516 - Part Shop Directwww.partshopdirect.co.uk