Where can i find an Aurum Beta S replac. stylus?

Find an Audio-Technica AT-95E stylus assembly, and adapt it. If you would like better, use an assembly from a Linn cartridge(K9 or K18?), or even better, an assembly from a Signet 5.0 cartridge. Some of the Signet assemblies exceed the performance of the Aurum Beta S considerably.

DIY skills are required, but you don't have to be an expert because the skill level needed isn't so high.

Good luck! :)

Manitunc is right; it's easy. In fact, it is so easy that it will be self-explanatory once you have the assembly in your hands. It's also self-aligning, so there is no need to worry about precision beyond the concerns you would have with a standard user replaceable stylus assembly for any Audio-Technica cartridge, which is really what you have. Clearaudio basically dresses up an AT, and renames it after applying their tweaks.