Posting the number would be helpful any chance it's on the filter molding ? I used a round K&N on my 38 and it conformed nicely but it's a one off I made also taller than 1"
I keep thinking there's likely a round K&N filter lik eyou've mentioned that will fit ? one would need the ID & OD With the OD of the Segal element being more critical.
measuring an original element would give the needed #'s