A little update. I received the Mont Blanc Starwalker Rubber pen that I got for a really low price to replace the one I thought I had lost and have since found. Side by side there are some significant differences. Googling how to identify fake Mont Blanc pens one way they say is the serial number underneath the clip. Sure enough, there is no serial number under the clip. Also, the cross hatch lines are thinner than the real one. The mechanics are also different. The fake one does not click into place like the real one when opening the pen for writing. Also, the way the internal components are assembled, it is different and the spring mechanism does not appear as robust as the real one.
What will I do? I suppose I could attempt to return it and get my money back. I'm sure the Seller would fight it and I'd probably have to involve eBay's police to get a refund. I'm thinking I'll just keep it, and use it as a very nice everyday pen and keep the real one for when I'm conducting real business. Ironically, the Seller did load it with a what appears to be a real Mont Blanc cartridge. It writes very nicely but the differences are real and noticeable. Hey, I had an idea it was fake before I even clicked on the Buy It Now button. We live and learn.