You could probably go the super cheap route on those. Sculpt a few different ears in Sculpey or regular clay, and make some simple molds with silicone caulk from the DIY store. Make sure it's a sulfur free clay though, silicone dislikes sulfur clay. The Von Akin you can buy at Michael's and Hobby Lobby will be fine.
Once you wriggle the sculpts out of the silicone, get your trusty rusty hot glue gun and squeeze hot glue into the molds. Once cool, they should pop right out. Hit them with some primer and paint away.
Then drag out those mismatched, hopelessly out of style, or just plain tiresome earrings out and bling those babies up.