I have a CHA47, which is an upgraded variation of the CMOY that I would be willing to sell. The CHA47 is a high current amplifier that has a cross feed circuit built in. CHA stands for Cmoy Hansen Apheared and if you search around you will find a lot of info on the amp. The amp I have has dual Burr Brown opamps and is supposedly built on the hansen circuit board. Although this is a small amp, it is not a portable amp. This particular amp is designed for home use and comes with an outboard Radio Shack 13v power supply.
It has both RCA inputs and a 1/8" input, but the RCA inputs sound much better. It has a 1/8" headphone jack. The cross feed circuit can be switched in or out with a switch mounted on the front. The price is $50, including shipping within the USA.