BrandonM Welcome to the forum. I've seen references for 3-Centa bottle caps selling between $30 and $40. Here's a brief history about the brand ... http://www.antiquebottles.com/3centa/
I don't see a picture of your cap. There is two different variations of the cap. I usually sell my three cents caps anywhere from $20-$35 based on condition. Below is the two different caps. Hopefully this helps