FWIW, Continental offers a compressor mount for the 550 engine and a small Japanese compressor fits very nicely on the back of the engine altho the battery has to be moved from the firewall.

The rest of the system is simply street rod stuff which is readily available from several sources.

You should be able to build a nice compact  A/C system for under 2 K.  Happy building.

Regards, Bill Hogarty