Yep, I would not pay a penny more than $800 and would probably pay closer to $700. These speakers are just not high end and they are used now. I paid like $1200 for some Polk speakers (rti series and I did not know any better back in 1999) and I was lucky to get $300 for them when I sold them. It is like all electronics. Only few brands/models will reallly hold their value, and a lower level speaker is definitely not going to hold it's value.
Personally I would be more inclined to have you buy some refurbs directly from the Harmon Ebay store and add a sub from SVS, HSU, Epic, eD, etc.