B Fish N has several colors in their ringworms (say FishUSA dot com to order)
Luck E Strike also has a several colors.
Lurepartsonline dot com again as several colors
It might help if you described what color "bluegill" is....
checked these web sites and it looks like oyster shell came as close as anything. thanks. and blugill was the color of the worm I had. they got stolen along with my boat several years back. they were a great finesse bait.
I looked and like some of their baits and inquired about air tail in bluegill. thanks much. I really thought someone might have some old stock they are not using.
They aren't 4" long but I cut some of the length off when I need a shorter bait. Try zoom trick worm. It is available in bluegill color and also I believe in a great color called sungill.