I purchased mine through the local distributor out here,
Chrisman's Driveline Components, aka
California Gear. I installed it when I first did my engine buildup/swap a few years ago, so everything was getting changed anyway. Hopefully, you'll find a shop that is both proficient as well as being reasonable when it comes to their rates. That is, if you can't do the job yourself; it's basically nothing more than a normal transmission swap. You'll have to get a new yoke for the driveshaft, but you won't have to alter the length, and the shifter will locate in the same hole as the original.