@elliottbnewcombjr In the sub $500 new cartridge market I am interested in knowing what options there are for boron or other hybrid cantilevers. For awhile there was carbon fiber but that was more of a cheap as chips option for Audio Technica.
Boron is not common at this price point, even used. Audio Technica makes one that’s (sort of) close - OC9XML, $600 new. There should be various used AT’s with boron out there. You can sometimes find a used Benz Ace or Glider at this price (boron, with either Fritz Gyger or Japanese MicroRidge stylus). A brand new Ace used to cost $550 (circa 2000s) but those days are gone and these models are no longer common.
That said - aluminum cantilevers can sound very, very good. Sometimes even preferable to boron, depending on the cartridge!