It's not as simple as just polishing it and taking a mould it will need release wax as well as a PVA coating to stop any risk of it sticking to it and you won't do that as a one piece mould it will have to be made in sections so it will release easy. However it can be done by someone who knows what they are doing spent quite a few years as a GRP laminator myself making moulds,boat building , finishing and flat roofs so know what's involved to do it correctly.
If you can get interest then get those who are interested to pay a deposit then get a mould made and start making them the mould will be the expensive bit as it has to have many layers of fibreglass as well as bracings to stop any distortion ect but once the mould is made to make the finished item not a huge amount of money at all
