I used to own a 1917 Smith. It had the Brazilian crest. I used to shoot it regularly. It did not require moon clips. I always brought along a pencil to eject the spent casings.
It was a great gun. I have since sold it.
Underwood made ~500 experimental (hence the "E") carbines.
I was told that they destroyed most of them, and gave a select few away to executives.
There are very few known survivors. Under twenty? I believe.