perhaps Sony has some help for you
https://www.sony.com/electronics/support/accessories-remote-controls
You may have downloaded something in the past, and a copy might be lurking somewhere on your computer. Try some search of the entire C drive, using a brief or partial term that might be in the name of a folder it created or a file it put somewhere.
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find Placette seller on hifishark, (none active) write the past sellers, perhaps they can help you
https://www.hifishark.com/search?q=Placette+Passive+Preamplifier