I got Speedway's 5x5.5" kit for $279. I called and spoke with them and they were very helpful. As said earlier, you can buy the bracket kit and then piece it together if you want (you will need the kit at a minimum as it has the caliper brackets and adapter bushing for the spindle). I think they use mid 70's f150 rotors and impala calipers (I have it written down in the kit in the garage). I compared prices at NAPA and it looked like it was going to run very similar in price if not more, to piecemeal it together.

I was planning on ordering it from them anyway (and did), and just called to check so if I needed to replace anything down the road, I could do so locally.

You could probably save some cash by junkyarding the parts, but is that a chance you really want to take for a safety item (for you and everyone else on the road with you)?