Amplified Fun in Portland for enclosure printing and drilling, Stompbox Parts, Love My Switches or Mouser for most of the pots, and generally SBP or LMS for the enclosures to drop ship to Amplified Fun.
Outside the US there's not really many options for Tayda. Musikding has some enclosures (and predrilled for their own kits), and Aliexpress too, but Tayda is unbeatable.