Welp pretty much drop ships everything except their meat birds.So while the breeds that many people listed are the most common (i.e. Sebrights, Silkies, D'Uccles etc.), TSC also seems to go through Welp at times. TSC has been known to have Pyncheons and even LF Welbars, both of which Welp stocks, along with RIR bantams and Rosecombs. Maybe it's a stretch, but I would say any breed that Welp carries, you could potentially get in if you're lucky. Most of the time however, they use Hoover and their chicks are of abysmal quality regarding the S.O.P.
The birds are bred by and are shipped from Privett's.