Thanks for clarifying Steelman!
Now that I know what to look for, the 1937 chassis book shows: 78-16635 "Spring, hood latch top tension". My 1938-41 chassis book also interchanges it to 1939 pickup and truck (not 1938?). There is an illustration in the 1938-41 book showing the similar 81A-16635 fitting 1938 std and dlx and 1939 std.
Fabricating should be straightforward, however this being a spring is likely some sort of tempered spring steel so getting a functional material will be critical.
If someone who has an original 1937 (or also an original 1938-39) could dimension my attached sketch and confirm if it is a spring steel (or bronze) someone could fabricate their own, and I will likely make a short run to have them available.