I'm looking at buying an LCR in the next few months, and to be honest - 8k is towards the top end of the prices for one. I've seen them from £4500-£9000 in all, so a wide range of prices. Of course, with this, comes a wide range of conditions/mileage etc, but I've actually seen some lovely LCRs for about 6.5k.
If you don't ask, you don't get. People are probably offering 6k etc because they have seen what they believe to be similar cars for that sort of money. Plus when you do any book-valuations on LCRs you'll more than likely find the figure is a lot lower than you're asking, so you'll have a hard job, more so in this climate, of convincing someone as to why that is the case.
Good luck though!