Because they are a smaller selling business than a retailer like Psyshop that sells far more different records, they may have more costs per record to cover, but I'm not sure this would explain all of the price. This is just speculation and I'm not trying to defend them. If they are indeed selling them at a higher price than they "should",
Now, this DUDE is not worked up, this dude has had enough of ripoffs in his life. When I started buying 12"s I payed around 7 euros for them, and today, EVENTHOUGH pressing costs less, you pay 10 euros in some shops?
I am asking myself, just WHAT is it, that has become more expensive?
Just to clarify, I wasn't against your initial idea. I think it's a good one.
Good luck with your endeavour. I wholeheartedly support it.