cannot find part numbers for above parts in model PSR-195 thanks don
The battery cover is no longer available from Yamaha. From the picture I see, it may be identical to this one, but perhaps a different color:
https://syntaur.com/Items.php?Item=5290
This measures 95 x 42mm - is that the correct size? This too is no longer available from Yamaha, but we do come across them now and then used.
The correct power adapter is this one:
https://syntaur.com/Items.php?Item=3281