The company is not listed in the Blue Book and the Standard Catalog lists only a few automatics that are rather inespensive, so I would guess the answer is "not much".
The revolver is probably an Iver Johnson. The grips were after-market grips, distributed by Siles.
Decoration
It was a WWI military knife, it should have wood grips and a blued finish.
on one side of the grips there should be a screw. take the screw out nad the grips will come off
Try egunparts
i have ordered grips for the heritage revolver. goto www.heritagemfg.com and choose the grips you like. they are not an exact fit but they work great. i would say they fit 99%. most of the parts will interchange between the rough rider traditional and most western six .22's.
Not necessarily. Grips could have been replaced.
value of belgium browning 25 auto baby blued with walnut grips
Midway USA
Abbreviated name of the company.
Try gun shops, gun shows, egunparts
About $100.