Easier to have it done by an expert ... cheaper and more satisfying to do it yourself. It really isn't too difficult a job if you take your time and have a good set of hogring pliers. Make certain to use new foam and burlap to make them comfy and good looking. I've done four sets and had to learn by just doing it.
you'll be cursing all the way to dinner with the hogrings, but you can do that on your own. you'll need an upholsterer if you design and cut your own seat covers. but of the aftermarket stuff just give it a go
+1 on the above said
Make sure you buy a set of hog ring pliers to put on the hog rings. They don't cost alot but are worth every penny. You'll be amazed at the job you'll do. However, your hands will be mighty sore after you finish. Not sore enough to prevent you from holding a nice cold beer, but sore none the less.