Avion studios sells just the power supply section, of the power supply. The circuit board that is. Its like $20. Then you have to buy a project box, 5 pin jack, power switch, power jack, 1/4" out jacks, fuse holder etc... but it works out great.
I am into the power supply breakout box for about $60, and it works flawlessly. Of course, I had the 5 pin cable, which would be another $50. I also had some other odds and ends, wire/jacks etc.
If you had to buy all of the parts, including the 5 pin cable, it would total about $125. That's pretty close to the VV cheekblock PS, which is really slick. If I would have had to buy the cable too, I would have went with VV. I just couldn't justify ponying up that kind of cash, plus shipping, so I build my own.