I think the issue is you are searching for the B7300 but your tag in the pictures is a B7200.
https://www.tractordata.com/farm-tractors/001/2/7/1272-kubota-b7200.html
Just for a little info to store for later. The Honda GC and GCV series doesn't have head gaskets because the basically don't have a removable head. The head, cylinder and angle cut upper crankcase are molded as one piece You remove the matchig lower half of the crankcase to remove the...