For the 80-90 dollar price range, check out the Fotrons, they are really good value, but their ratings do what they are advertised. You may want to wait until OKWolf or larva sees this. They are very familiar with Fortron and could recomend the right unit for you.
Personally I run an OCZ520ADJ, but that unit runs 139 dollars. If you can go that high, it's a very good unit, but I suspect you need to keep the price down. Fortrons are actually very good units.