You can tell the quality of a power supply by the weight of the supply. It may say it's 200 watts higher, but if it's less weight than the 500 watt Cooler Master, then it's not a quality supply. The more heat spreaders in a supply the longer it will last. That being said what brand is the supply you got from the repair service? Often time manufacturers warranty their products and all you may need for a new supply is an RMA number, which you may be able to get with as little as a serial number from the supply.
If the supply went dead three hours after you got it, I assume you already contacted the people who did the work? I know personally I would come back out and replace the supply after hours for the cost of gas, or let you bring it to me and replace it at my location free. Unfortunately any hardware can go out, and if it is going to it's probably something like 10x more likely to do so in the first 48 hours of run time in my personal experience. Hopefully you got a quality supply from the repairman and can RMA it yourself with little or no additional cost to you. Either way I wish you luck, you got lucky in that the first supply didn't overvolt anything so much that it caused damage, that isn't always the case when a PS dies.
Static electricity can kill a PC, but if the repair man had done so it's likely that it would never have booted back up. They may make you clip an anti static strap to a grounded piece of metal in a college course. In real world conditions, simply keeping a hand on a metal computer case that's touching the floor has always been ample grounding to prevent that stray charge in my experience. More likely is that something, let's say a capacitor, in the power supply wasn't up to specs and blew preventing the supply from lighting the rest of the rails.
