On the plus side, it's stylistically similar to his other prints published by Kyoto Hanga-In. Also, at the bottom of page 18 of the "C" catalog (see the link below in the "Reference" section) there is a note saying, "There are two more horses which make a pair (Vertical)". Later in the catalog, on page 33, there are 2 vertical format prints shown as framed. This print is one of them.
On the down side, the signature and seal bear no resemblance to the seals and signatures on the other prints more solidly attributed to Sonan Noda.