Integrated amps, need some help

For around $300 you might find used Arcam alpha, Audiolab, or Cyrus amps. IMHO these are all better than NAD or Cambridge. Granted they will be nearly 10 years old at this price, but they're usually built to last at least 20 years.

Nuthin' wrong with NAD stuff, terrific value. If you'd like a tuning section as well, the NAD7100 Reference receiver (my first pick) or the NAD7250PE would be great choices. The 7100 would likely sell for around $250, the 7250PE around $175. If you don't need a tuner section, why not pick up the original classic in quality audio, a NAD3020 integrated for around $150? You may want to keep an eye open on Ebay and Audiogon as this gear does pop up frequently.

p.s. if you're looking for speakers to mate with his gear, look into B&W DM302 ($150 used) or B&W DM303 ($200 used)

The Cambridge Audio integrated to get used is the A3i. It was designed top to bottom by Michael Creek. Much better than the A500 and better parts (High current R-Core transformer, Sanken transitors, MosFet devices). Has a MM phono stage also. Was a HiFiChoice Best Buy for years. See the reviews at audioreview.com. The A3i is the only way to get a recent Creek for under $300. It is a very conservative 50 watts at 8 ohms (70 watts at 6 ohms). One was tested out at over 70 watts/8 ohms at the rated distortion.

The NADs are also very nice, and are a good choice (C340, C350). I have owned both (prefer the A3i). You could also consider the Rotel RA-970, RA-971, or RA-972. It all comes down to personal taste.

I'm not sure how set you are on integrated, but you could pick up a rotel pre amp for less than 200 bucks used and then a little 50 wpc solid state amp that is 8 or 10 years old. It'd be fun to play with and leave you with plenty of room to upgrade in the future.

...surf arround Cambridge integrated amps throughout www.audioadvisor.com.
they have an unbeatable prices for new mid-fi equipment.