You are correct. The kits aren't cheap. The best prices on the Billet Specialties kit I found at Summit Racing. The kit comes in four flavors depending what accessories you are running. The basic kit with only the alternator runs right at $2000. The big kit with A/C, PS, and alternator is a glorious $2600. The other two kits sit close to $2300. Being that the kits with PS have a mini pump, you have to also buy a remote reservoir for the PS fluid. When talking with Paul Clark, who makes the hydroboost kits, he stated had some experience with this pump, their hydroboost kit and a reservoir in Matt Delaney's '71 Cuda on the Powertour that was causing aeration. I don't remember what brand of reservoir he told me, but his complaint was that it was just a regular can with no filter or baffling. They fixed the problem by putting a pot scrubber in the reservoir.
Anyway he was suggesting using a reservoir from PSC (
www.pscmotorsports.com ) with the mini pumps. They had one other issue with one of the idler pulleys giving out, but they attributed it to not being torqued correctly on the install.