EG Bates was down the road from me in Plaistow, and I think Leach Marathon where up in Stratford somewhere. All my bikes are from Nottingham/Nottinghamshire though (Raleigh, Carlton, Paragon,) which might be a bit of a detour too far! Other than that I'm in.
Sounds like a great idea.
Here's some ideas for the tour -
Ephgrave -
150 Upper Clapton Road,E5.
Hetchins -
798/800 Seven Sisters Rd, N15.
Gillott -
177/181 Southampton Way, SE5.
Hobbs of Barbican -
34 Barbican.
Claud Butler -
Manor St Works, Clapham, SW4.
Youngs of Lewisham -
248a Lee High Road, Lewisham & 290 Lee High Road.