The rifle seems to me to be a rework of an NRA 1903 sporter, based on the rear sling swivel base and the way it is attached. I don't know that it's the work of G&H, but the sidemount base, barrel band, front sight ramp and hood, forend cap, pistol grip cap, etc. are typical G&H features and the rifle looks very similar to photos in Michael Petrov's book. The folding leaf sights are not necessarily G&H. Also, I don't recall seeing a G&H with forend checkering that doesn't wrap all the way around.