For the small value caps, we use either Silver Mica, or ceramic disc.
It is not true that ceramic discs suck.
It has its own sound.
For example, in the OTS series of amps, the small value caps are mainly ceramic discs, and not silver micas.
The originals did have the same type. We compared using both types, and Alexander knew his stuff for sure.
For silver mica, we use mainly Cornel Dubilier brand. Sometimes, we use old ones from El Menco, or those ADI, SAHA, etc. Sometimes, I get em cheap in bulk, or from closures, that is why.
For ceramic discs, we used RMC brand for quite some time since I had lots. Now, we usually use whatever brand it is mouser carries. I think they're Taiwan or China made.
But hey, check the others and see what they use for these!
Thanks!
Nik