usually you buy gp32s with the overclocking upgrade(which i think your talking about). If you haven't bought your gp32 with this it is much easier for you to do it yourself. It is a very easy mod, and you will probably take beter care of your gp32 as the past shows. Just look at Azure's gp32.
If you still want to send your gp32 of to get modded check out www.gp32z.com.