Here's a link to the rifle.
https://www.gunsinternational.com/g....cfm?gun_id=100810570&contact_sent=1

The more I look at it the more I think it was done by James V Howe or at least influenced by him. I found pictures of a Firearms International Mauser in the 600 range with a similar shaped stock on Gunboards at this link. https://www.gunboards.com/threads/firearms-international-fn-mauser-sporter-rifle.449129/