more info...although the information isn't on the site, the PriceWatch says: 
Samsung 512MB true PC2700 pc 2700 pc-2700 DDR333True PC 2700 chip - 184pin memory DIMM
that answers the overclocking question...and with the lifetime warranty, it's gotta be good OEM stuff, right?
I've been hunting around a lot, this looks about as good as it's going to get for awhile...and the shipping is cheap, $1.54 flat rate, 3-4 days to ship, but if you're not in a hurry, doesn't sound bad atall.  Thanks qck, I'd overlooked this one in the glut of stuff on Pricewatch.  
 
They've got a couple others too, like this:  512MB DDR 266MHZ (ECC REGISTERED) MAJOR BRAND LIFETIME WARRANTY.  for $146 and change...is ECC Reg worth the extra bucks?