How large are your parts? If they are under 60" or so it can be digitized very quickly. Otherwise simply drawing 2-d work is very quick.
If you can scan them on a regular desktop scanner, the program at the link below looks interesting.
http://www.graphconllc.com/
If you can get copy of Rhino and a microscribe digitizer, it is a slam dunk. The digitizer would be the real cost. Ed Kuhn at Remtek does about as good a deal on digitizers as I've found and is very quick to give a small shop a hand.
The URL is
www.remtek.com
We are in Dallas and do this ( and 3-d) as a normal part of our business if you decide to send them out.
Best of luck,
Phill Pittman
digicarve@verizon.net www.masterwerkes.com