The Standard Catalog of Firearms says:
Standard Arms Co., Wilmington Delaware. Model G. Chambered in .25-35, .30-30, .25 Remington, .30 Remington and .35 Remington with a 22 inch barrel and open sights. Integral box magazine and closable gas port that allowed the rifle to be used as a slide action. Blued with a walnut stock. Produced in limited quantities. Circa 1910.
2003 U.S. value for one in very good condition was $750.
The book doesn't mention a Model M.
A Google search came up with a couple of hits including a Youtube video.