The ones that i can remember well are Fender, Selmer and Vox, they were the only ones that appeared via the media.
The British rock scene was very young and i know that there were a few home made amps being used by bands that were just starting out and did not have a lot of cash.
Have a look at this site http://www.california-ballroom.info/ it was the place to see all the up and coming bands of the day. You will see if you look some names that made it very big like The Who and the Rolling Stones and a lot that you have never heard of but it was part of the start of it all.
Enjoy
Ken



