Anywhere, as wild camping in Scotland is very much encouraged unbelievably! The West coast is totally unforgettable. Look into the North Coast 500, although I did 2000!

Wildcamping heaven I believe

As I understand it you can pretty well park anywhere where you're not going to be a nuisance...

There is a website that I'm happy to recommend as they, in turn, link to us for pub stopovers Nomad GB - if you whittle down the choices to just 'potential rest stops' as in the image you can see there's loads of options.

As said before, anywhere, layby, side of the road etc is fine