I got them from Kustom Coach Works, but next time Im up at the RV I could write down that info and let you know. I did not pay any attention to the brand.
As an alternative to busting them out, you could pull the fixture down about 1/2" and then holding the fixture, twist off the lense. Be careful you don't knock off one of the springs (which actually hold the light in the ceiling), but if you do, they easily go back into the little tabs they are stuck into.
Monty & Janet - 2007 Alpine APEX 40 MDTS
S/N - 75715 - Retired - Master Certified RV Tech