Greetings Zyaath,
The rare gears, other than the Wanderer gear, really shouldn't be called rares anymore since they are now easily obtained by doing the SA quest. Like anything else, the prices on gears have a wide range. In the old days (2 years ago) I would sell the rare gears for around 500K. Now maybe 5 - 10K.
Are you doing the quests to get gears? If you are let me know as there are a few common ones that I'm having a hard time getting and I'd buy them from you.
*Tips Hat*
Bucko the Kid