"Body appears very good"...
Never judge on appearances alone.
If the meter coupling chain is broken, I would say there is a good chance that the camera has a few other problems too! These are now very, very old cameras, and the older they get the more unreliable for critical projects. Those from 1969 to 1975 are now the worst for major failures. The last-generation cameras with lots of improvements from 1991-1992 are still going. The chain is not required if you are manual (hand-held metering); indeed; you can focus and shoot with nothing on the top, just squinting down into the focusing screen! The coupling chain though is required if the metered prism is present on the camera. Repair entails disassembly of the lens mount and shims (and these cannot be reused), rethreading of replacement chain (e.g. TigerTail multistrand beading wire), testing, reassembly (with new shims) of the lens mount and finally collimation for correct focus — with a lens on. So it is not really a DIY job. This service can easily exceed the value of an old camera, so it is a matter of weighing up risk and reward.
My two P67 cameras, both dating from the final generation in 1991-1992, have OEM chains in-situ. It is essential to learn the specific way of removing and replacing the prism and lens so that tension is released on the chain. Too often new users unfamiliar with these cameras hit the interwebby with a saturating welter of stinging words about the cameras because they did not bother to understand the correct way of using them! Lots of things can (and do!) fail: the meter coupling chain, the winding mechanism, the film counter roller, shutter (capping), mirror solenoid (mirror sticks in the up position, or stops half way or does not work at all), shutter speed decay...it's a long list of things that can go wrong, and the older the camera, devoid of any routine or essential servicing over its undoubtably long life, the much higher the risk is of cascading failure.