I agree with logan. The Workhorses are great all around ballasts. I use them in all of our jewelry showcases in our store where we run T6's. They are cheap, lightweight, and don't get very hot.
They also run all kinds of stuff. Look what that Workhorse 7 runs. PC
's, T4's, T5's, etc... All the way up to T12. Last ballast you will ever own as long as you don't go to MH
, you may be able to find it these at your local electrical supply/lighting store store. I would call around to see if they stock them so you can pick one up. It would be a lot faster than ordering it over the net and should be cheaper.