For anyone who used to use https://opposedforces.com/ for their parts numbers, I found this website that may be useful:

https://jp-carparts.com/subaru/carlist.php?maker=subaru

Looks like it covers most Japanese vehicles if you go to the homepage.

 

Partsouq is good also, you can add your vin so it gives exact parts schema for your car

 

Amayama is better still.
https://www.amayama.com/en

Websites use the Subaru Parts Databases, however they vary in which version they are based on.

Opposedforces was suitable for upto Model Year 2008

Jp-Car parts looks as if it goes to about Model Year 2013 and generally for JDM spec models only and used to be very very slow during the week.

Amayama covers upto Model Year 2018 for worldwide variants

Partsouq similarly covers upto Model Year 2018 for worldwide variants