Yes, you can do it yourself. All you need is a few carbide bits, sandpaper cartridge rolls, and a nice die grinder. You can also buy them here:
Porting is pretty easy so if you don't need your car for a while I would just do it myself. Line up your gasket on your manifold, mark the excess material, and then just shave it off with your bits. Smooth out any obstructions and watch you don't get too thin, you'll hear a higher pitch if you are. Follow up with the sandpaper cartridge rolls and smooth it out real well. Exhaust porting should be very smooth, intake should be a little rough(if you ever do an intake).