You might want to look for good distribution channels where there are communities built in parenting or making food fun for kids. Teaming up with them (think mommy bloggers, educators, etc.) to review your plates might provide an additional boost if you can offer them some sort of small incentive.

Additionally - have you contacted the 100 who have bought and asked them 1) how they found you 2) What about the product enticed them to fork over their cash for what you have created? Finding this out can lead to ways to offer your plates in areas where your target customers go/visit online as well as if they would recommend their plates to family and friends.

For paid traffic options -- you would want to be mindful. For example the CPC on google for, "melamine plates" is over $5 a click but you might be able to play around with keywords so that even low traffic terms would a) cost you less b) might provide a better conversion because it could be a feature or benefit of the plate that peeks their interest.

I hope this helps as a push off! More than happy to dive in if you can provide more specifics.