For the dinette, the choices are:
904 - 13.5v 0.69a 5000 hour
906 - 13.5v 0.69a 1000 hour
912 - 12.8v 1.00a 1000 hour
I replaced my stock lamps, which I believe were 912s, with 904s because they were too bright with the shore power plugged in. If you boondock or want brighter light maybe the 912s would be the way to go.
Bulbtown has pictures:
http://www.bulbtown.com/912_MINIATUR...BASE_p/912.htm
http://www.bulbtown.com/787_HALOGEN_...BASE_p/787.htm
It is a minor source of irritation to have so many different bulbs in the trailer. I carry a bag of spares and even so I don't have everything. Nonetheless, you can get something that will at least work at most parts places for all of them, even if it is maybe too bright or not bright enough.