this will be a balls ache to do, but for safety sake it has to be worth it.
i would hope this is gonna be a uk standard tho, as i agree with the changing of fill nipps after every pa event is gonna be a hastle, a real hastle. esp if you have pa, then masters the week after.
also as to cost, this should be really low as in no profit, just cost, if it is gonna be a requirement, then u have us over a barrel, i for one wont appreciate extortianate nipple prices, if they were, then u would really fail here as most ballers work on a budget.
this is my personal opinion.