Thanks for the link - I just ordered a replacement and a few spares. Looks just like the bulb/reflector assembly that burnt out in the handle of our coach.
Update: Bulbs ordered & delivered - I replaced the burnt out one and it's working great. Also found the sealing rubber "o" ring broken on the handle where it seats into the base and was able to find a suitable replacement among the selection of "o" rings in the plumbing area at my local Ace Hardware store. Makes a big difference in the stairwell.