Yeah you can use any fixture. Well assuming they are the same size. If you are looking for something cheaper hit Walmart or Home Depot for stuff like this. I got a ballist that holds two 24" flourescent bulbs for $9 at WalMart. Can't beat that.
The bulb rating should be okay. Just when you are setting up the cage remember to set-up areas that get close to the bulb. I would probably say about 6" in these areas.