Wardsmit, you can modify many of the bigger Do-It jig molds into a tail spinner. I've done it with some of the big Style H heads, the shad heads, and the big Ultra minnow head.
Start by finding a shape and style you want. Now pour about a half dozen with just a piece of like .041 wire (3") out the rear where the hook would normally exit.
Now, bend up a dozen pieces of u-shaped wire on a round bend pliers.
Now on each one, drill two holes in the top and bottom about where you think the line tie and the hook tie should be. Insert the u-shaped wires in 5-min epoxy. Make each one a little different.
Now rig them up and head out to the lake. One of them will be the balance that you want. Guard that one with your life and throw the others back in the lead pot.
Put that one back in the mold and mark where the wire loops should be. Carve out the loops with a dremmel.
You will have to bend the wires by hand, but it's not too bad if you make a little bending jig.
I hope I didn't make that sound too difficult.