What exactly are you trying to power with this 1 or 2 channel amp you're looking for? I've seen in a couple of places now where you're asking for something that is 600w MAX or less.
Well ~ not trying to be condescending but most car audio enthusiasts know that max wattage rating on anything is a rather irrelavent number and good for nothing more than marketing purposes.
Example: My set of older Pioneer Premier TS-E6990 6" x 9" 3-way ovals are rated for 70w RMS....but they're also rated for like 240w MAX or something assinine like that. I have no doubts that if I were to send 240 full-range watts (unclipped or not) into them for any length of time I would soon smell smoke and cease to hear any output from the bynines.
So....back to my original question....what are you wanting to power and what is its RMS wattage rating? This info would be much more useful in determining if a potential seller has something of any use to you.