igniton interrupt/shift cut-out

[YamaCruiser]

Searching for a shift cut-out magneto, part # 6T0-8135F-00-00. I have had no luck in finding it. Yamaha says it has been discontinued. Is there a substitute? Looks to be nothing more than an earth magnet with a hole through it. I have found close matching sized mags but i can't seem to drill through them. The mags keep shattering.<br />any help would be much appreciated.