The best place I've found is
Classic and Vintage Bulbs in South Australia. This guy has the lot and the best prices I've found so far. He also has the P700 lamps at good prices. It may not be listed on his web site but he has a huge range of original Lucas lights. I bought the L691 & L692 tail lights and indicator lights from him as well as an original number plate light. He also has original style mirrors.
The Classic Revival body is designed to use MGB sized trim rings which are the same as the originals.
Cheers