The light is enclosed in a probably 12” x 5” glass cover and air can’t circulate. It probably does get hotter in there than the rest of the house’s fixtures.
That rules out most of the compact fluorescents on the market -- they don't like to get very hot.
But a regular incandescent bulb should really be fine, and a
rough service (130V) bulb would do even better. Pretty much any
home center or
hardware store or
lighting shop will have those on the shelves, in 50W or 60W versions. For higher wattages, you may be stuck with ordinary bulbs.
I was at
Princess Auto on Saturday, and purchased several
rough service bulbs there for 88 cents each (sale price). Some shops want as much as $3 for the same bulb..
Cheers