i had a similar problem when i went to put an RS steering wheel on my 95 impreza coupe. i had to buy the clockspring from an RS so that the steeringwheel would plug in, but then the plug on the dash harness was different too, at least for the airbag, the horn plug was the same.
there are 3 sets of wires and 2 plug points in the steering column
dash harness <------> clockspring <------> steering wheel
in your case, i dont know how hard a proper clockspring would be to find. if you can find one, then you only have to worry about the dash plugs, which are more likely to be the same. otherwise youll have to cut and splice the plugs from your existing steering wheel to the wires on your new steering wheel, so they can plug in. or you can go without a horn or airbag
another option: if you can find a proper clockspring but the airbag plugs still dont match, then you just need the end of the airbag plug that it WOULD plug in to and take that and make a jumper/patch from your old/existing clockspring plug and then you could just plug it in without modifying your dash harness