Here's a close up of a genuine 499 and the 355 vacuum can from the same date range as the pictures of the "499" above, This distributor is not restored, but the housing has been dipped in carb cleaner to be able to see what was under the 46 years of grunge that was on top of it. That's White Out rubbed into the numbers to give them contrast for the pic.
I've seen a lot of supposed originals over the years - you get to the point where you can tell what you're looking at with a little inspection and comparison. I don't believe I would invest a lot in the one pictured above.
Just my opinion -
Regards,
Steve