It's a standard K6-2 core, which means it has no on-die cache. But it was made for a laptop, which means it runs cooler than a desktop K6-2, and is probably a great overclocker. I bet you'd get 550-600 MHz out of it with a good cooler and 2.2v.
From memory the 2.0V K6 non-plusses were hand selected (not literally) so while they may run at lower voltage there is no guarantee on overclocking. I would suggest that it may hit close to 500 though.
Yeah I did take a look, but they all referred to the K6-3.
I wasn't sure whether this particular K6-2 had the 128k cache. Doesn't look like it does - oh well, I may get it anyways.