Best bet is to get yourself a Computer server power supply. Because they are made to operate servers they are made to a high quality and very high reliability, unlike the hobby stuff which is often cheap junk in comparison. Even second hand server PSU's are very dependable.
The easiest one to use is probably the HP DPS-600PB. They are very common and can be picked up off eBay dirt cheap. A single DPS-600PB will give 12V and 48Amps, and costs about $20 off eBay. Conversion consists only of soldering on a couple of bullet connectors for DC output and jumpering a couple of pins together to turn the unit on, 30 minutes work at the most, you dont even need to take the case off the unit to do it.
PS, there is a photo of my old dual DPS-600PB PSU in the first photo of this thread
, along with my new 'mega PSU' the ESP120.... The lights in the neighbourhood dim when i power that thing up