If it is the larger "senior" or in some cases marked as "military standard filter" that you are looking for, Fram's web site lists the C31P filter as current. I went in under 216, 235, 261CID engines for "1952 Chevrolet/GMC Truck Pickup" in their application guide. They also list the C4 for some cases for the same application. The C4 also comes back as fitting the 239CID in "1950 Ford Truck F1-3". I found nothing in their site that gave dimensions of the filters to enable comparisons with your old filter.
I used to use the C31P for my M135CDN, about 1985 it was still a stocked item at local auto parts shops.
I hope this helps you.
(The thread
http://www.mapleleafup.org/forums/sh...&threadid=3786 gives other compatible filters).