sp7 keyboard

I need a replacement keyboard, found a good deal barely used from a smashed SP7 for power supply, case and most important the red keyboard - wanted to double check its compatible to the SP4? I cant find any information for backward compatibility - only forward! Thanks!

Keyboard Case I am searching for a keyboard case that protects my new SP7 but is light weight. Hopefully with an attachment for SP pen. I’ve seen some online that are either too heavy, the attachment for SP pen is too small making it very difficult to put pen in and out. I would like the...