NAPA Auto Parts sells 4 Season's A/C Mfg parts and equipment who is the largest supplier Of a/c parts in the US. They also sell under the Murray brand. 

Works like that many places -- I keep my old Volvo Dealer work Tee  handy - I used to work in the parts department. Wear that to any parts place , ask for the wholesale price -- youll get it -- cause you are "in the know" .

 The Secret is out!

All sorted. I borrowed a "union proud" tee-shirt from work, already was wearing jeans becuase it was friday, and walked straight on in and they didn't ask any questions. Got everything I needed.  

There was several "wholesale only" signs on the counters, doors, etc too. The power of a tee-shirt eh. Going to keep a hold of this and use it next time I need "wholesale only" parts LOL

Don't go in to the Yellow Jacket dealer, call from your office and have it delivered.  Make sure they know you are an engineer and this is test equipment based on readily available HVAC parts.  ay with a credit card.

Good call. I'll get a tap from them. I have heard too many bad things about their gauge kits though - unless they changed the design. It just seems crazy to have to buy a $50 gauge set for a seal which is replaceable and known to crack and split.

Harbor Freight will have R134 charging equipment (even a very good electrically driven vacuum pump.) You can't get individual servicing parts like seals and hoses (as far as I know) but I think the whole charging manifold is something like $49.95 (and less if you apply one of the commonly available 20% coupons found in newspapers, magazines, etc.)

I can't find my R134a tank tap (valve) and also noticed the seal in the end of the yellow charging hose is split. I don't have time to get these parts on-line (need functioning AC by saturday evening), so where is my best bet to get them locally on Friday?

I managed to get to the local Autozone just before it shut, but unfortunately the genius behind the counter pointed me to the plastic cheap kits that just ram more refrigerant into the existing AC system. They don't seem to sell anythign of any real use...

I know last time I tried getting parts for my furnace locally, none of the local HVAC specialists would serve me unless I showed them a card (maybe going in wearing office attire wasn't the best move in hindsight) - I don't know if they would help me with this - or even have the R134a tap which is designed for the automotive use anyways....

Any pointers or advice would be appreciated!