Didn't see a functioning webpage for them, but i did find this site which apparently used to sell the same thing and according to the specs in the listings it's a 1.14" diameter spear in 24 or 34" length.
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Which is odd, not quite 1-1/8", not quite 30mm. I don't know what exactly they were using when they made that, or if the spec is just wrong, or if that spec is the ID of the socket in which case it's probably a 1-1/8" bar.
I think a regular 39" bale spear would have about the right 34" working length, but you'd have to get somebody to lathe the end down to fit your socket. Or cut out your socket and weld in the one that comes with the bale spear. Or just modify it some other way. But if that company is out of business it'll probably be tough to get an exact replacement that requires no fabrication.
I'll be the first to admit im a hack in a lot of ways, but i also think if it's already broken you're not making it any worse, so if it were mine id probably take out all the other spears, stick the broken end of this one in the middle socket, and try to use the loader to bend it back a little, then id weld it back onto the base and just see how long it lasted.