I'd say your chances for a 5E action/forend are nonexistent. As I recall they only made about 155 Grade 5 NID's and as someone has said--the vent rib guns had a different action shape in the area of the barrel extension--so--non-vent rib guns can't use these barrels. I'd offer them for sale as being able to fit ANY grade Vent Rib NID 12 bore. I'm guessing they could bring up to $1000 depending on condition, length and chokes! Use gunbroker or gunauction.com.

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