Indy,
The lawsuit which resulted in the U.S. paying Mauser royalties mostly involved the Mauser top insertion clip, not the action itself. Though there were certainly some similarities between the actions, there were enough differences to avoid that issue.
The 1917 Enfield was considerably different from the Lee-Enfield action, with more resemblance to a cock-on-closing pre-98 Mauser action.
Interestingly, both arose from experience fighting enemies armed with pre-98 Mausers, the US looking hard at the 1893 Mauser and the British at the 1895, after coming up against them. Both also embodied a few local ideas/prejudices, such as the US insistence on a magazine cutoff and the British wanting a big action to suit a high-velocity 7mm, so as to really reach out there, after having troubles reaching out with the early Lee Enfields in South Africa (mostly due to issues with sights, but that is another story).
It sounds like your hunt went well. It is a good lesson in the value of practicing quick follow-up shots. Everyone hopes not to need them, but sometimes that ability to throw them in quickly and accurately makes a real difference.
