~$1,200
General rule of thumb by my experience... LLL.com is worth at least $5,000.
I think .org LLL names are superior to their .net counterparts... however, both tend to sell between $1,000 and $2,000.
You won't have any trouble selling it - there's always demand for short domains. But the only thing that works against this name is the fact that it has the letter x in it. That instantly devalues it.
Since you're looking for a quick sale, I would advise either putting the name in the short domains for sale section (you would need to upgrade your membership), or put it on eBay to get some competitive bidding.
Best of luck with your sale!