Pretty sure they were from Princess Auto - 2 1/2" trailer light grommets that I simply cut to fit. They work perfectly, look almost OEM.
I had also read somewhere that later compressor brackets are different, but the 471-0204 fit beautifully in my '83. Amazon said it would fit so I was not...
Says Japan, but who knows. It was identical to the original OEM unit I removed. Call JT and cancel or ask them to price match. My experience with them has been good, but they can take a long time to ship.
Could just be a bad o-ring somewhere. Easy to change them all out on a deflated system. Well, except for the ones on the evap, but still not that bad.
Did you change your drier when you switched to 134? The desiccant in the stock (or replacement) Denso drier doesn't hold up to 134, apparently...