I think $1000 is a very good offer for this name. Obviously you should try and hold out for more - but after negotiating if this is their highest offer i'd go for it.
- Remember - don't rush the negotiations, if you have to remain silent for a few days, do so. If it's a genuine end user they will be coming back and taking your hand off with the name.
I think try negotiate more. It is worth more I think but if thats the max you get I still think you should sell and reinvest that money in a better way.