just checking, is the earth wire connected behind the airbag steering wheel centre? or are the wires damaged? Are you sure the steering wheel airbag is the issue and not one of the others, seats etc? any other issues with the comm2000 unit.
Cheapest way is go to a pick a part style wreaker and find another from similar year. basically if you have all the options on your Comm200, i.e. cruise control, stereo controls, central locking rear window wiper you need to find a car with same options and same manufacturer, if you have Valeo find another Valeo, if Delphi another Delphi. Check early C4 C5 Xsara and early 206 307 406 407
the following should be suitable if yours doses not have all the features the extras wont work, i.e if you dont have a rear window wiper the function will not be connected, same with cruise control it wont work if you use a unit with more features.
624276 6242.76 6242 76
6239V7 6239.V7 6239 V7
6239L5 6239.L5 6239 L5
6242F9 6242.F9 6242 F9
hope this helps?