I don't recall what type they are, but I did buy a bunch of LED bulbs for those lamps a year or so ago.  I ended up just replacing the lights altogether.  I still have some of those LED bulbs if you want them.  They worked great but I wanted new fixtures. Send me a PM with your address if you want them.

Hi, I recently ordered the following through Amazon; 

The warm white version is a big improvement over the standard white. The Admiral fully approves. Price was very reasonable. Work great so far.

New G4 Bi-Pin Omnidirectional Landscape Camper RV 2W LED Light Bulb (6-Pack)[Warm White]. They came from LEDwholesalers.com

They're G4-based halogen bulbs.  Old technology in that they are both energy hogs and hotter'n hell. Suggest replacing them with any good-quality LED, as noted by other posters. 

Personally, I replaced mine with Marinebeam red-white bulbs, which are automatic red first on the same switch. When I flick mine on them come on red, then if I switch it off and on within 5 seconds, they come on cool white.  Nice for night vision:  https://store.marinebeam.com/9-led-dual-color-switchable-back-pin-g4-bul... You'll probably have to trim off some of the wires as they come too long.  The only thing holding them in the fixture is friction, so you just pull them out.