I was given this piano because a few of the keys weren’t working. I open it up and pull all of the keys and contact connectors to find a few contact traces missing and corroded solder points. When I turned over the keybed contact boards all of the diodes under each dead key was either missing or heavily corroded. I noticed you have the board listed but out of stock so I was wondering what diodes I can get to replace the bad ones because I can’t find the specific ones on the board (1ss133ta).