This is what Lon Paul built for me, using an original Rigby slant box, stepped ring, single square bridge Magnum Mauser action and stock, with a new barrel and sights, including a Zimmerman Rigby style cocking piece sight. .350 Rigby Magnum, serial number 3528.

This is the "before" condition, with the takeoff barrel screwed in by hand.

A 400/350 Rigby is in the works, also using an original Rigby action.