Can't help you in Myrtle Beach. If you want to drive about an hour north to Wilmington, I can recommend a mechanic that is honest, but any A/C work is going to be costly.
To give you an example of how the prices can run....
I recently obtained a 94 GMC Jimmy that has a bad compressor. I was quoted about $750 to replace the compressor and everything else to get the A/C working properly on that one.
Good luck.
_________________________
Matthew C. Hinson
1929 Ford Model A Phaeton, 1976 Ford Country Squire
AACA, MAFCA, MARC