Go to the Fulham site at: www.fulham.com
and look at all their ballasts. They are considered the best and are reasonably priced. They have all of their wiring combinations listed on the website.
I believe AH Supply, the best place to get PC light kits here in the US, uses Fulham Workhorse ballasts. They are at www.ahsupply.com
Both these sites are very educational.