That is going to take some serious luck to find!
If a 2120 owner has his tractor for sale with a BH, he is very unlikely to split the combination.
I found a BH years ago for my Ford 3400, from a dealer who had replaced a cemetery hoe.
I waited 2+ years for that one to come up for sale, and I never saw another.
My 3400 was a larger machine than the 2120.