The problem with the 150w they sell at lowes and HD is it gives off more heat then lumens.

They don't sell what you need. Check the local paper classifieds ads to try to find a used one. Look on eBay too you can get a good deal there but shipping is pricy.

You are looking for switching ballast but with the little amount of money you have I doubt you will find one for that price. You may find a HPS and pick up a multi spectrum bulb (like Hortilux) that way you can veg and flower with the same bulb. There are also conversion bulbs where you can use a MH in an HPS ballast or HPS with a MH ballast. You just can't use a standard bulb with a ballast it's not built to work with.