You paid 70 for it, knowing what VC does and gives when used, so obviously to you its worth that much. I think I paid 25for once close to two years ago, now there 10 or less PD's. What I'm saying is something is only worth what it's value is to the buyer. I get what you mean about being ripped off and new players which in this case seems happened, but at the same time you must of wanted one enough where this price justified spending 70pd on one. I'd say their worth is 10pd much like any hitless event weapon.
This is why I don't buy stuff from people's shops that don't have base prices on them. They ask the buyer to say a price in hopes they will offer more then what they wanted. Every item in a shop is their because it's expendable to that person, and should be a price as to what it would take to let go of said item, like their is in stores which we can't offer a price for a bottle of water we pay what the seller asks.
If the seller asks 70pd and you pay it well that's what it's worth to those parties. Your not forced to buy it. You can farm 70 PD's pretty quick in WOI too. It's when new people are trying to sell something for example a red ring, and someone who's been here awhile offers 10pds and the new person doesn't know its worth 10 dts (most are 7-8 now) that I really consider someone being ripped off.