I have used Anthonys bulbs for more than 12 years, good focus, and none have burned out --
http://www.classicandvintagebulbs.com/page2.html I get them at Hershey, not the cheapest, but made by a car guy that cares, I have the pre-focus bulbs for my 36(what the 39 would use), and I just got 35--50 watt for my A to replace the 35-35, i can still run the 50 watt with the generator.