While you're at it, you might consider switching to T8 bulbs. You'll
need to replace the bulb holders as well, but you'll get electronic
ballasts automatically.

I've had it with 22" & 32" circs and 6"-48" T whatever.
When ANY part fails, I pull the guts and add 1-4 standard
edison base sockets, and screw in 5w to 32w CFL's as needed.

Cost less that replacing the bad part and my box of $2
5/13/24w cfl's (HD 6 & 8 packs) will now replace everything.

-larry / dallas