Nevertheless, I've looked into this William Moorhouse a bit more.
He married in Howden in 1823, described as a gentleman.
At his children's baptisms he's described as a merchant in 1824-27 and 1840-45, and a gentleman in 1829-38.
He's in Baine's directory in 1822 as a lime merchant, rope maker and vessel owner (listed under 3 separate categories), and in Pigot's (1834) as a lime merchant. So there's no evidence there of him being in a uniformed occupation, though he does seem to have been important locally.
He himself was baptised on 28 Jun 1790 in Knottingley; Knottingley registers are damaged and only partly legible, but it was a chapelry of Pontefract and the baptism appears there too.
The baptism and burial I found don't fit the dates on the silhouette, and while I suggested earlier that the name may have been wrongly remembered, you'd then have three items that are similar matches and none that are exact, and you're in grave danger of twisting or disregarding the evidence to match the hypothesis.
So while William Moorhouse of Knottingley seems at first sight a tempting possibility, in the absence of any other evidence he can't really even be that.