I just swapped all the locks on the fiance's jeep to a matching set I pulled from a jeep I was parting out, not a bad job at all and much easier than having multiple keys (her jeep had one key for the ignition and another for the doors/hatch. If you're sourcing new locks I'd try to get an entire set and not just the doors/hatch.
Try a junkyard or a part-out. Hatch lock isn't bad to replace, there's a single stud/nut and then it pivots out with a little work (I found it was easiest to just replace the entire handle/lock cylinder assembly). Taking the first one out took me a while, but the second time around was about 30 seconds once I had that nut off.
Alternatively, you may be able to have your existing locks re-keyed by a locksmith to match the ignition. I've read that people have done this but I'm unsure of cost or availability.