For new ideas, and new products - potential buyers love to see the inventor is invested in the idea, and hands on in showing their belief in it.

I'm not sure where you're located - there's good advice above about approaching restaurants and distributors ... but there's also an opportunity to go to the source. If in Sydney get down to the fishmarkets (Pyrmont and Chinatown) with your kit in tow and beg them to set up a little desk, with your product, their oysters and you attract customers to them with the product. Get up early enough and get keen enough and many restaurant owners and buyers will be at the markets. It'll be smelly, dirty and rather sh|tty work to start with, but you'll be in the middle of your target market, and might well be able to sell these to the kind of market that thinks a home 'oyster party' is good fun (... no different to the home 'chocolate fountains' that seem to sell like hotcakes periodically...)