Most shops won't install an O/R pipe for legal reasons. Someone may chime in about one, but you may want to post this to the regoinal forms. The install isn't too bad, you can do it w/ basic hand tools.
It takes about 30 minutes in your driveway, and the poster above is right there is no way a shop will install an off-road mid-pipe for you, the fine is outrageous for them if they get caught
WD40, some swivels, some extensions, and a gym membership.
I used a 10" extension, a swivel, and a 6" swiveling extension to get mine.
That bolt was a pian on my car, which only had 3k miles on it when I did it. Just give the WD40 a chance to set in, and you should be able to get it off.