If I had them they work fit any tractor as long as I could make mounts or brackets to secure them to.
They are probably from an old IH tractor as you mentioned.
I found out on another forum that they fit "1950's standard/wheatland and orchard models. W6, O6, W400, etc.
Some friends of mine have a restored WD6 (diesel). Might see if they would be interested in the weights. I have no need for them other than possible ballast on an attachment.