I think they sell the RA-4 and C-41 chemicals to mini-labs that's the reason they make thier own up. I've seen both the Agfa E-6 and C-41 kit at the Steeles Henry's store. Only one or two kits at a time so I'd guess it would be very easy to have it sold out at any time. BTW Agfa uses different names for the stuff so the box won't read E-6/C-41.
George I've been mixing up C-41 for awhile and that's pretty easy. The E-6 formulas don't look any harder really. Between all the formulas I have I think I can avoid buying too many extra chemicals.