Its hard to say how much it could cost to machine the heads. Its one of those things you gotta get a couple estimates for. If you're interested, here's some info about it.
http://www.aa1car.com/library/ar996.htm
If the heads are flat resurfacing shouldn't be required. If it is, you would have to take a look at the block too. A good 3 angle valve job would probably be all the head work you would need.
As for valves, I'll need to do some more searching, but I think I can find some prices with enough digging.
