One way is to see how much the repop ones are going for and either double or triple the price. Seeing as they are just a few bucks a piece I could see 5-10 bucks each being a decent price. Although somethings are harder to resale. If you are looking for something that is correct for your car then I think that would be a great price to offer. But take my opinion with a grain of salt because I am a tightwad..