LH .. I made a quick check in a couple of old catalogs (Wholesale Distributors) and came up with the following:
Hal-Fly "Jelly Belly"
Columbia "Jelly Bean Jig Fly"
Not sure who made "Mr. Wobbly Flys" (same body had wobbly rattlin eyes)
I think the "Hal-Fly - Jelly Belly" was the first of this type bait
There are several others that I cannot think of right off the top of this Gray Hair Head.
Halfly was the original. Jacobs now has a couple molds to make them a couple different ways. One just makes the bodies. The other you place a jighead (with tail material tied on) in the mold and inject the plastic body.
They are pretty easy to make . Get some soft plastic maggots . Put them on the hook . stick it in the vise . Take a pair of hemostats shove the grub up against the head clamp . Tie the fly , then release the hemo shove the grub down over the tie .