Parallel Flow Condenser

[dmjlambert]

Here are my facts:
R12 is $25 to $35 per can on craigslist when it is available. By the time I drive across the county for an average pick up of a can of it, consider the total cost to be $40.

Here is my question:
Is there a certain price point at which using R134A is better? Or is R12 worth buying even if it goes to $50 per can? Is the case of 12 cans I see listed right now for $300 something you guys would recommend I run over and get right now?

Rambling:
I would like to have an A/C that works fine when it is 110 degrees outside and high humidity. In my 1969 CST/10 have a stock 350 engine with A/C cab and original A/C in poor condition, so I would like to refresh the system. I have a stock clutch fan. Engine cooling performs fine under all conditions, stop and go traffic, hot outside, or whatever.

From what I have seen on the web including this site, my research tells me using a parallel flow condenser is of upmost importance if using R134A. My wife's modern car uses R134A and the A/C blows so cold even if it is hotter than hell outside, I can't run it on the max cold position without wearing a jacket or rolling down a window. So I would like to think that is achievable in my truck. I'm thinking the thing that would prevent me from achieving that is a regular condenser. I don't want to end up with crappy air since I'm getting ready to spend big bucks on this.

More questions:
Does anybody know of year/make/model of car or truck for which a brand new condenser can be ordered from a parts store, and which is parallel flow and which will fit in our trucks? And the maker of any adapter tubes with fittings that will adapt, perhaps fabricator who is familiar with these trucks and what it takes to get superior A/C working?
Does anybody know if Vintage Air or Old Air or any of those full kit makers actually has a parallel flow condenser as part of their kit?