Cut your own for less than half price and save yourself the trouble.
Buy a pack of large or medium herring from Rhys Davis. While it is just partially thawed, use a SUPER sharp knife and cut the angles and lines of the strip on the whole herring on each side. Fillet the strip off the carcass. Ready to use. Insert into the strip holder and fish away. If you want to get fussy, do mirror image reverse cuts for the angle on each side.
If you are really bored, do this...or if there are few fish around and you really need to capitalize when your gear may be eyeballed by just 1 to 3 fish all day.
Before Coyote spoons really hit the market in the late 90's...strip and firecracker herring was gangbusters and a great way to get excellent mileage out of a pack of bait.