I think the guy on the left is playing through a Matchless DC30, but I can't really tell because he's standing in front of it. If it is a DC30, and it's Mark Sampson era, that's a really good amp. Supposedly one of the best ever made.
Here's local darlings Borrowed Beams of Light:
Here's local ne'er-do-wells us. Note that Youtube metadata points out This video has no honors: