Rolling block identification

[old turtle]

This looks like a Whitney New System action. It is shown in the Frank de Haas book Single Shot Rifles and Actions page 163.

[Bouteselle]

Thanks. I'll take a look on ebay!

[marlinman93]

This looks like a Whitney New System action. It is shown in the Frank de Haas book Single Shot Rifles and Actions page 163.

Nope. NOt a Whitney New System. That action had pins with the tab on them that swung under the center retaining screw. Unlike Remingtons, or early Whitney-Laidley that used a pair of pins and a center flat bar to retain them.
The New System Whitney also had a trigger guard integral with the lower tang, not separate like this one is.