Richard,
Look at the flyer you posted again.
Note the phrase "Walnut
finished wood". Also look at the edges of the open case pictured in the flyer. Notice that the wood looks just like the wood of any mahogany case you have ever seen. The TR cases were mahogany stained with walnut stain.

Kinda ironic, really- the cheaper version came in a cheaper wood than walnut stained to look like walnut, and the higher priced guns came in the cheaper wood that was not stained. Maybe they ran out of stain while the engravers were working....
Note the typical mahogany grain and texture on this case-
Lid of same case.
This ain't walnut. It is mahogany stained.