Resin moulds are cheaper to produce than Lead or plastic, and there isnt the problem of soaring metal prices.
So it should cost as much as the current brain bug with enough wedge left over to pay for the new mould. But if the rest of the range increases in price (As seems likly) then it'd be silly not to price accordingly.
Not very useful I know, but the important thing is, that the process shouldn't add anything to the cost.