Rolling Block Help

[Hanz]

A cleaning rod hole was filled in with a dowel:

Remington Rolling Block Carbine by Doug Hansen, on Flickr

The Upper tang is proud of the wood and this is the best cartouche on the buttstock:

Remington Rolling Block Carbine by Doug Hansen, on Flickr

Remington Rolling Block Carbine by Doug Hansen, on Flickr

Remington Rolling Block Carbine by Doug Hansen, on Flickr

It has a neat rear sight:

Remington Rolling Block Carbine by Doug Hansen, on Flickr

Remington Rolling Block Carbine by Doug Hansen, on Flickr

Remington Rolling Block Carbine by Doug Hansen, on Flickr

So, what do you think it is and what do you think it's worth? I'm not interested in it but I'd like to help the gun shop out with some better information than I can provide on my own with my limited experience with these neat, old rifles.