Dear Bob and mid-60s Buick coolcats, . . . . 
Bob, what engine will be driving this this Vintage Air compressor? One big problems with Vintage Air is finding a bracket to support the Sanden compressor. Have you solved this problem?
Edouard, I had not thought that far ahead yet, as it's still pretty far outside my budget 
If you decide to go the Vintage Air route, I can probably give you some pointers because my trusty 1965 Buick Special wagon has been upgraded to Vintage Air (she used to only have "roll down the windows" air! 
). There are some tricks to get Vintage Air to work with a 1964-5 Buick A-body (perhaps others.)
Unfortunately one serious obstacle is mounting the Sanden compressor. I had a custom big-block Buick engine built for my wagon and the engine builder managed to splice the Sanden compressor bracket into a Buick big-block bracket for the AC compressor of the day. You might need to do the same if you want to stick with the Buick 340 that's in your 'Lark right now.
Of course you could always go for a Buick big-block!! Somebody is now making brackets for the Sanden compressor for that engine. Unfortunately, it may be a bit of a hard sell to insist you need a Buick big-block just because it is the only Buick engine right now with an "off the rack" bracket for the Vintage Air compressor!
Cheers, Edouard 
Haha, well swapping motors to get the right bracket is a bit overkill for me
. Besides, my 340 has already been rebuilt and never fired, so I'll be sticking with it for quite some time. Also, I work with Laser Measurement devices for a living, so I'll probably just 3D scan the mounting holes of the 340 head in relation to the existing pulleys and then scan the hole locations of what ever pump I use. I can then use that data to reverse engineer a bracket that works for both! Easier said than done, but still in the realm of possibility
