when i was racing i had a catering sized baked bean tin for a while, then graduated on to a tupperware bowl until a kindly scrutineer told me i couldnt have tupperware as it wasnt strong enough (i think he was just miffed he had never been invited to a tupperware party) so using the tupperware as a mould i made a fibreglass repro of it..
i realise this is of no practical use to you.. but i think sean is on the ball, look for something that can be adapted and you will save a whole lot of dosh.. if you want to spend dosh look up 'aluminium spinners' online, im not sure theres many left but they could knock up something quite cool i would have thought..