Thanks for sharing your "Utility" set with us. If you will post the shotgun barrel length, I can give you the actual factory number designation for the set. As to the choke, I have not found choke identifying marks on any of the guns I have researched. Also, I have found no choke designations other than "Full" in the catalogs. I had 3 Utility sets, 333 was the highest number of my 3. These sets are rare. Let me caution buyers who find the 219 rifles with an extra shotgun barrel, especially without a shotgun forearm, for sale, and listed as original "Utility" sets. The assembly numbers must match on all 5 pieces. Thanks again for sharing. You have a very hard to find set.