#2
why dont you just get them from a local shop or online
Gibson 58 VOS, Gibson Rich Robinson ES-335, Fender Strat, Fender RoadWorn 50's Tele, Gibson LP Jr Special

Marshall JTM45, Fender BJR NOS
#3
Not many places inb the UK have a good selection of the above, plus I'm just testing my amp with various valve combinations so want to do it on the cheap....
#5
I have checked e-bay, and most on there are dual or quad sets, or expensive NOS valves....