RAF Wing Commander's mount
Like an F9F Panther had an incestuous relationship with an F11F Tiger (with was originally designated as F9F-9)...I just finished a book about Neil Armstrong. He bailed from a Panther in Korea. I wondered what a Panther would look like with a J-65 with A/B. No wonder.
Maybe your Griffon engined Wyvern is a successor to the later Merlin engined Seafire.