Probably depending mainly on whether it was fitted as original equipment from the factory. If it was, (and replaced by a non standard non-airbag after market wheel ) all you probably need is a 190 airbag steering wheel. Best would be the sport (smaller diameter but not much in it) steering wheel for originality. The rest of the circuitry and crash sensors ( on transmission tunnel behind ashtray???) should still be there. HOWEVER and its a big however you want to check that the airbag circuit is disabled before fitting. You cant make any mistakes here or risk the consequences of a faulty airbag deploying as you drive along or during fitting. Problem with a retrofit is knowing the PROVENANCE/HISTORY OF THE AIRBAG. Best to buy a new replacement airbag unit to be absolutely safe once you have got a repacement steering wheel. Once fitted and enabled then the SRS warning light (yellow?) should illuminate briefly on switching on the ignition and then go out after several seconds showing the circuitry is active.
If your car didn't come with an airbag from the factory upgrading would be very expensive since you would really have to go for all new parts to get a reliable system. You could cost it a your local dealer but it might be difficult to even source the parts. Sorry.