Suburban third row bench seat

[bchamb3]

I know this topic has probably been talked about on end, but I can not find what I am looking for in the forums. So, I will ask anyways. I am wanting to purchase a third row seat for a 68 gmc suburban. Someone contacted me saying that they have many seats for sale but are not too familiar with them and their pricing. Factoring in the condition, what is a fair price to pay/offer? Thanks for any help!