Thanks for the replies guys! I probably won't sell it, it feels so nice in-hand it'll be my go-to SLR for a good time to come, I should think! The Tamron is a 28-50 f/3.5-4.5. It's an 07a, if that means anything to you... It's a great range, I shoot in that range an awful lot, but it's no good, sadly, the aperture's a bit sticky. Never mind - the 50 is fine! The hunt for more good FD glass has already started, I had to exert an inhuman amount of self-control not to walk out of my local camera shop £400 lighter and an 85 1.2L heavier!
I'd love to go nuts with a load of paint stripper and a paint stick, but it really doesn't look like it's stamped, as far as I can see it's just a heavy-duty transfer, the paint is raised on the lettering, not sunken... I'll take it to an art shop and see if they can identify the paint type and recommend something for me. I'll let you know how I get on. Cheers!