Have just updated my PM66se to a PM7003, after one of the channels in the 66se gave up the ghost.
I think the 66se was a good amp, but the 7003 is far superior.
the 66se retailed at around £400 when I bought it, and I picked up an ex demo one for £270. Im pretty sure this was around 1999 and it was 'end of line' stock, so they are over 10 years old now.
If I had to buy one again i probably wouldnt pay any more than 50 quid for one. That may be me being a bit tight!
If you like Marantz you can get a 6003 for £250 and the 7003 for around £350 if you shop around.