Commiserations about the covid jab - my wife suffers similarly, and it's not nice.
As for the silhouette, it's just occurred to me that if it was done in 1827, the chap would only have been about 36. Isn't that a bit young to be an admiral?
And the name - I still think it looks more like Monkhouse than Moorhouse, but people make mistakes: if they knew that 'my aunt married someone called M...house' they might have got a few letters wrong.
But if it is Moorhouse, and we're not looking for an admiral, I've found someone who may be of the right sort of status in Knottingley, near Pontefract - a William Moorhouse.
1861 (RG9/3433 fo11 p16) - J.P. for the West Riding of Yorkshire
1851 (HO107/2329 fo533 p32) - Commissioner of the Queen's Taxes, Ship owner, Landed Proprietor & houses, Lime Burner (?) and Mercht.
1841 - haven't spotted him, but some of his children are at the same address as 1851, without parents (HO107/1310/10 fo8 p9)
I can't spot a death for William in or around Knottingley in 1863, but there's one in Mar qtr 1865 in the Pontefract district - but I haven't managed to find either a will or a newspaper announcement to match either of them.