I would go new with a kit. A nice new shave ready razor, a proper strop, and a brush and soap if you don't have that already. This should last you several months and give you a good idea whether you like to use the straight blade or not. I would wait to get the stones until you find out if you like it or not....and if you do, then get yourself some stones etc.

I would much prefer one decent razor. I don't think buying a beat up retread is the way to start...but it's your face


Best of luck,
Rob