green bearings

ive had a set for 12 years in my 8.75. one has gone bad, and i still havent decided on wether or not im going 8.8.

id like to finish the fall out before tearing major into the car anyway.

so im going to throw another set of green bearings at it.

ive looked all over, and seen a bunch of places selling them for a unch of different prices.

im assuming that the green bearings are a factory application from something, and therefore have a NAPA replacementy number. am i right?
if not, who has them cheapest ( or at least inexpensively with good customer service?)

thanks
michael