I am troubleshooting my AC system at the moment, trying to get it working again. The car is a '68 Dodge Coronet with factory AC. I am tracing a very small leak. I added some of that UV dye to my system. I subsequently checked with a black light and couldn't find a leak anywhere.

So now I am replacing my radiator (it had a disagreement with the clutch fan). As I was removing the radiator I noticed small amounts of UV dye on two of the condenser coil tubes. Specifically it's limited to two of the 180° bends at the end of the heat exchanger. I looked closely, but could not find a specific leak point. I also noted that the AC system is still holding pressure, so it can't be a large leak. There's no damage at all to the condenser coil (like rock hitting it), but it is original to the car. So my question is, do they commonly develop very small pinhole leaks after 44 years? Easy to fix or buy a new coil?