$300 - 400
Depending on condition and extras of course.
I bought a used Sub 2K 9mm Glock at the Holt road gun show in January for $350 and came with a 10 and 33rd mag...deals are out there, you just have to be patient and diligent.
The guy was asking $375 and I thought that was too high, so I talked him down
Thats interesting because I have been looking for one for about 3 years...just found one used. In have 2 different ffl friends that have not been able to get them for several months.