[rpcope1]

Noctua fans are usually a good choice (though I think their industrial line is better, especially if you can get a deal on the splash proof IP66ish ones). That all said, other than having extremely good lifespans for ostensibly a retail oriented fan, the other thing they tout (the low RPM and quietness) sometimes doesn't work well when you're replacing something much different like a high RPM Delta fan. The Noctuas may not push enough air, especially if there's a controller involved. I've had to build add on fan controllers before where whatever it is won't spin the fans fast enough until they heat up too much, which makes things even more fun. Especially for a PSU it's probably worth looking to see if there's a major difference in airflow (and at what RPMs), as it would suck to have your fixed up PSU cook itself because it's not flowing enough air.

Other less prominent vendors often do make easier drop in fans, that often have very good lifespans that might be easier to adapt than Noctua. Sanyo Denki fans easily will long outlive even Noctua (but don't typically play in the retail space); Delta and Dynatron also usually sell at least decent parts that are much better than whatever random chinesium fans lots of stuff come with. All of the above have much more variety in the profile of fan sizes and configurations and I would probably be looking through their parts catalogs to see if they don't have something that's a better fit (they often do).

The only other interesting thing is that I have picked up is soldering seems like a good idea in cases like this, but at least in bigger setups I've seen solder joints fail because of vibration. Maybe not an issue here, but crimping is usually a much better solution for connecting things that need to have a long life and might be vibrating like something attached to a fan.