Hi J, seller
autumnimports on ebay often lists Bulbophyllum sessile for cheap; I think she sometimes has alagense too. You could try asking her what else she has that would do well in that situation, she seems to have a ton of different Bulbo species.
Carolina Orchids is another good source for Bulbophyllums and I think they carry a few Pleurothallids as well. They usually have a lot of unlisted plants so be sure to ask if you don't see what you want.
Hope this helps!
--Nat