Can you identify this diode or its logo? I'm hoping to at least learn who manufactured it to narrow my search.
Searching for "2020R Diode" shows several options, such as On-Semi MUR2020R in the correct TO-220 package.
This may not be the exact manufacturer, but it will likely be a compatible alternative. There are many series numbers that are made by multiple manufacturers, including unnamed fab houses.
Based on the logo I'd guess it's most probably from a Chinese semiconductor fab called Hanking Electronics.
Their main logo is slightly different, but the H part is a pretty good match. I tried to find some examples of smaller package products from them, but yeaaah. Good luck finding a supplier, I can't. Seems like these days they're all about the MEMS.