Wheel re-dishing
 

I would like to have a rear wheel re-dished at one of the local bike shops. It's 27 X 1 1/4 with cassette for gears. I would like to know if I can reuse any of the parts off of the cassette, what I will need to buy to make it a complete, yet safe transition to fixed gear, and approximately how much I can expect to pay.

Thank you in advance for any input.