hmm..dont see why not..may want to measure the thickness first to make sure you have enough for the enitial turn, and some extra incase it doesn't turn out so good. As long as its an even flat cut and the rotor stays balanced, it should work.
I think thats the replacement price...I hope...it averages around 10-20 bucks to have rotors turned, any higher price and your paying to much. It usually takes about 20min a rotor. I just take mine to O'Reilly's, drop them off, get lunch and pic them up and pay my 40 bucks to have all four done.
It can be done but it's a pain in the ass. First you need mount the rotor and indicate, on the lathe, the part of the rotor that faces on the truck's spindle to probably .0005" (maybe more but check the spec for total runout). Then without moving anything cut one face. If you can change the cutting tool to face the other side of the rotor without dis-mounting it then you don't need to re-indicate and just face making sure you don't thin the rotor to less than the min spec. If you can't and have to flip the rotor over then you need to indicate to the already cut side to .0005" (or less) and cut. It's a bunch of time and the reason why brake lathes were invented.