They seem to have their own separate product numbers too. For an example of a site that has both, see the listing at
Bertram's Inkwell on the second line. They are priced the same. What is confusing though is that some sites, such as the Cross store of penhero.com, lists very different prices for these two pens. It is very confusing, to say the least.
Note that when you go to the cross site, only the tuxedo/silver is shown. But I somehow eventually stumbled upon the tuxedo/rhodium, which I had to relocate by using google:
Tuxedo/Rhodium Plated. The model number is 556-2. It is mentioned that it is not available for purchase

Here is the link to the
Tuxedo//Silver Plated, whose model number is L556. You can buy this one

I wonder whether this just a name change between the old and new models? Note that Penhero has some closeouts for "old models" that look identical to the new ones. Is this all just reflecting the transition from the old made in U.S.A. models to the new Far East made ones? Perhaps there are slight physical differences or legal reasons to distinguish between old and new? it all looks very mysterious to me