Yeah, Sam is lifefly-outdoor on eBay. You can click his name and his profile has a link to his eBay store.
He has fluorescent lime eyes back in stock, which are a nice yellow chartreuse.
4mm fits the 1/16th, 3/32nd and 1/8th ounce Do-It walleye head. 1/4th and 3/8th are 5mm, 5/8th and 1/2 are 6mm.