that's a pretty good pickup. unfortunately, i dont know yet what the differences are in indexing, when you compare .com to .net and .org
i do know that one of those 3 extensions are still likely to enjoy an advantage to indexing, vs. the more exotic extensions that exist in the market right now.
that being true, that should sell, absolutely no lower than $500 (better to hold it than to even think about selling it lower than that). and it's value, if you succeed in marketing it to the right end-user, could even reach several thousand dollars.
nice pickup