are the hard parts available to get it up & running? reciever/drier & the valve on the firewall etc. Not opposed to converting to R134 if recommended. can a person rent the gauges/hoses/vac pump & do it at home? tho it would be my first time with this. I have my eye on one & I think the A/C is non op & A/C is pretty much a dealbreaker for me. thank you for your time

I think it depends on how original you want it to look. both vintage air and classic auto air make complete kits that you can piece meal if you like.
if the underdash still works, most people find that works better than the aftermarket parts, and just replace the underhood components.

I will check em out

My 65 Barracuda is a factory air Commando car with the knee knocker unit under the dash. I will more than likely buy a new aftermarket system that will fit up under the dash where the factory heater box is now. I just don't hold out a lot of hope finding parts for a 56 year old under dash AC unit.....lol.

I had my eye on a 66 A with a complete factory A/C non working in very good original shape but I actually prefer a 64 or 65 & if everything will likely have to be replaced with aftermarket stuff maybe I should pass on it & look for a suitable 65/66 & add the whole aftermarket kit. does this make sense or should I stay with the all original 66 & replace with aftermarket stuff the items that need replaceing. this is my first time refurbishing an A/C so I am clueless here. EDIT is going with r134 a good plan?

I think it will depend on a few things.
The aftermarket setups don't move as much air as the factory setups do.

Being in Texas, I would rather have the factory setup under dash, refurbed (classic auto used to offer this service, not sure if they still do), with new underhood parts.
Now it isn't an apples to apples comparison, but I had a 66 coronet with factory air, you would have to turn down even on a hot summer day. but it was a HT. My 65 convertible with the total aftermarket system, running full blast just barely keeps you from sweating.
But that is also a 100 plus day.
I don't know how hot it gets where you are.

It is probably going to be as much work either way.

Cost might be cheaper for an all new system instead of piecing one together. Figure 1500 overall for a whole system.
No idea what refurbing the original runs.

Originality also is a consideration and depends on how much you care about that.

Thanks Andrewh. Yes I was in a caddy decades ago & it would freeze you to death on full blast. It doesn't get too hot here. I will call Classic air & see what they say. I kinda like the idea of original but I may have no choice. It is going to be a job either way