I am sure Phil Royle keeps his 4/4 outside under a cover - I cannot remember which one he uses though. Might be worth a PM.
I`ve had a couple of Metex outdoor covers from Hamilton Classics - good & non scratch - but quite bulky.
The latest one which I ordered from the NEC in 2019 is by Covercar - an Italian firm - about £200 with "ears" for the mirrors and Morgan logo in gold printed on. Breathable, non-scratch, waterproof and much more compact - think Spandex for cars. I was dubious when I saw them but am very pleased after a year . The MD in Italy has Morgans - so understands. Choice of colours and made to fit. Apparently used by Prancing Horse and other Italian supercar manufacturers.
www.covercar.com email info@covercar.com
Hope this is of use. If you PM me with an email, I can send you a picture.