Just as an FYI I doubt you would ever need a completely new axle do to this problem. If you didn't notice it leaking until you started to hear clunking most likely all you need is a rebuild.

There's a shop near my dad's shop that does axle rebuilds. Had them do rebuilds when I had my CRX. Take it apart, clean everything, new bearings, pack with grease, new boot and clamp, reinstall. Only takes them 15-20 minutes and maybe $50 per axle. I forget the price honestly but it ain't $800, ha ha.

Unless you physically break something or let it run dry for a really long time a rebuild should be possible. Even if you go to a parts store and buy a "new" axle it's 99% likely you're getting a rebuild.

Granted EVO's are rare compared to a Honda so just save your core and take it to an axle place personally. Have them rebuild your OEM part so you know for sure you won't have any fitment issues that could happen with mismatched parts.

 

You would be surprised at how long people will let a little clunking noise go before they fix it, well with anything really.

And I've had axle rebuilt incorrectly and with the wrong sized parts used, so there is no guarantee that you won't have any fitment issues.