Yikes. That's a remarked part -- the style of printing on the top is wrong, and the date code is nonsense. (0448 would indicate it was manufactured in late 2004, but Rockwell Semiconductor was spun off as Conexant in 1999, and they stopped manufacturing this part many years before that.)
Oh, that's interesting (and way outside my knowledge bubble). You reckon it would actually work as a 6502, or it's remarked from an entirely not-65xx CPU?
Both are possible. I guess there's a 70% chance that the chip is not a 6502 at all, nevertheless still a 30% chance that the chip is salvaged from trash and remarked but its silicon die is authentic.
There's a decent chance it's actually a 6502, but the actual part that's under those markings could be any one of a number of 6502s from many different manufacturers.
