If it has holster wear then $500 is too much..For that price you can get a refinished P6 with the bells and whistles..
If you want a SIG P6 with holster wear then get one from J&G Sales for $349.00 add $50 for shipping and FFL that is aroound $400..Or go to Gunbroker.com and search for a P6..I saw couple of finished ones that really look sharp.
I have a P6 and I love this gun, very reliable and it definitely has SIG DNA in it..It is so fun to shoot at the range and it has never failed me.
Two more things you need to consider if you want to carry this gun..The magazine holds only 8 rds..So most people are OK with it, just to let you know..Also if the barrel is not modified to shoot hollow point ammo, it will no feed properly. MIne is not modified for that, and I tried hollow point by Fiocci and I got a jam every 2 rounds..However I tried a box of MAGTECH FIRST DEFENSE 92.6 gr SCHP [1,330 FPS] hollow point and it went thru with no problem..I guess the parabolic tapered shape of the bullet made all the difference, the bullet profile resembles that of an FMJ bullet and it fed up the ramp quite nicely..
If you want a P6, get a P6...It is one fine SIG gun. Hope this will help.