you will be really pressed to find a sailboat with dive compressor for that period of time - bareboat...
Sailboat dive compressors are very expensive, require maintenance and take up a fair amount of room to say the least. Having one installed on the boat often raises the insurance $$ as well...
You may want to look at the classified adds in ScubaDiving, Sail, Cruising world for private owners willing to work with you.
I would think a 36' will still run you $2-2.2K weekly, if you can find one. I don't think liveaboard dive boats are that much, and many have decent privacy, for a boat.
All the best