If you want the look of a vintage system, run the head unit - the piece inside the interior.  The most important differences between an R-12 and an R-134a system are the compressor (different elastomers for the seals) and the condenser (it has to be larger to compensate for the reduced efficiency of the refrigerant).  These are all common components.  The compressor mentioned earlier is a Sanden unit - not a Sandeen.  It's a standard swash plate design adapted to many installations; its modularity is what makes it an attractive alternate for vintage air applications.  

None of this is cheap.  To have a functional A/C system in an older car is going to cost you five figures - any way you cut it.  There are no shortcuts, as there has to be a compressor and condenser change to make it happen.  If you can find someone with a stash of R-12 (and yes, it does exist) the bill will still be within 80% of the cost of converting to R134a. Irrespective of what path you take, you're still north of a grand to get an A/C system going.  

I used a underdash unit from a 60's mustang or fairlane, put a sanden compressor and vintage air condenser on, it works well. It would be better with the correct metering device for the 134 a, but I'm no expert on that. I also switched a 87 t bird over to 134a, put the correct oil in the system, its been fine for 6+ years. I could deliver ice cream in that car. 

my son has in fact taught himself how AC basically works from reading an old service book belonging to his grandfather.we'll keep your suggestions in mind when he has enough dough to move forward on this project!Mark