Those IH/Cub Cadet weights also work as front weights for a Farmall Cub. Take a look over on Ebay what they sell for - $100+ a set and they fit inside of USPS flat rate boxes. I had dozens of them sitting around then discovered this new outlet - with my new found fortune I was able to go out and buy the correct JD cast 12" rears.
The outer weights are definitely Allis Chalmers or Simplicity weights. It looks as though someone stuck two different brands together to make them heavier. I don't have any idea who made the inside weights, but if they work go with it.