How have you folks been shipping new and/or used oil filters to other states in the lower 48 of the U.S.? I have some extra new filters I want to post to eBay, but the shipping looks like it will push the price too high. I'm seeing about $7+ per filter by the USPS, and that's by weight and small box dimensions. Padded envelopes would be cheaper but seem like a bad idea due to likely damage. And that's still spendy.