While I do admire you wants - I will say that finding a backhoe for that 40 year old tractor will be just short of finding the needle in the haystack! Not saying you cannot find one - but it will be damn tough.
Those tires look huge for that tractor! Did you install or you buy that way?
We’re not looking for bad advice . We’re also not selling our tractor. This is the internet. MANY B7100 backhoes exist and we’re here to help track one down.