???
Not sure what you are saying here. In fact, I read it several times. Seems like something got left out of your post......maybe ?
The part above, in blue. No clue on what that means.

RockAuto is a website like Amazon, they produce no products.
I have never heard of an axle breaking under normal use. Ball bearings wear out.

Detroit axle is a rebuilder, contact them for your custom axles!

Spending the extra for ARP bolts, Double Diamond gears etc more than pays off in longevity and ability to withstand many times anything originally intended. My recent plans for any engine builds will be an 8.5 compression blower motor. It will run all day on regular pump gas and easily handle periodic full blown nitrous hits or other random idiocy. All of the extra cost is easily made up for in general longevity and a usability.

is there a part number? maybe a couple from different manufacturers?
I want to look for it nearby
don't forget, I have a high shipping cost, so the final price of a bare CV joint can be much lower

I see that ZZP sells stage 1 performance axles. Anyone use them or something similar? I'm only going with a few inches of lift but I want something that won't be stressed.

SS axles are different won’t fit LS/LT

Their LNF axles(which are currently sold out) are for the SS. They won't fit your car.

Their 2.2/2.4 axles are for manual transmission only.

Their LSJ axles, I don't know, probably won't work, but you could nose around the Cobalt SS forums to see if it's been done.

Hub end is different for the LSJ different spline count!

I can't help thinking that it would be better to use your energy to work on other things and unless they are already broken, solve the axle problem once it proves to actually exist.