Anything is possible.....if you spend enough money!
Sure you could change all the locks on a '94 but it sounds expensive
I'm curious as to why you can't get a key cut, as 94's did not have smart keys. Are you having them done at a hardware store? Try going to a locksmith (take the car) and explain the problems you've had. They will charge a little more, but much less than changing all the locks, and the keys will work.