Robinsons Foundry, Crooks, Govnors bridge or go to the Classic Mechanics Show at Stafford next weekend, last year someone had new tanks, panels for them for sale.
I bought one new about 1979/80 Reg GTA951V.Good bike but output shaft broke when 7mth old and kick start mechanism had already been replaced by then.Pulled like a train but brakes not too clever.Cam chains can be a problem.To be honest,I wouldn't spend much of anything on it.Money or time,though I don't know if they are colletable or not.Just my 2p worth.