Believe it or not, I'd buy one from a local clone shop. That way you can actually SEE the chip, look at the stepping, etc. before you buy it. Plus, some of them don't do as much business as the on-line retailers and might have a better chance at getting a good OC'able AXIA. You might pay another $20 than a take-your-chances-online purchase, but it'll be a heck of a lot cheaper than one pre-tested to overclock.
- G