yea it is possible but not a good idea....the car wasn't meant to have air bags and may not have the clearance needed to put them in(driver to wheel clearance)
but yea u cud put them in but wud take sum 1 noin wat they r doin...ud hav to put sensors in the bumper as well as get a later model steering wheel that has air bag in it already.... u cud hit up a junk yard and get the parts... but air bags r EXTREMELY dangerous to wire as well as highly susceptible to voltage changes.....which is y ur supposed to disable them wen u work on vehicles with air bags
as far as how much it wud cost depends on wether u do it ureself or hav a shop do it.... i wud def recommend havin a shop do the work....