After writing the long note about the Lonan Scarffe's, I had a rethought on Lynda's James, born 1806. He does appear in Onchan 1841 (age 35) and 1851 (age 44) census's, and he seems to appear again in 1861 as a widower with the 2 younger children (last one called "Emma") but the age is way out (43).

I now think the burial in Lonan of James Scarffe age 27 on Nov 28 1831 is the son of James SCARFFE and Catherine KNEAL, and not the son of Thomas and Eleanor. This makes sense with the statement in 1833 that James "died some time ago a bachelor intestate" with the reference to father James. The age 27 fits perfectly too.

This means that the James bapt 23 Jan 1803 son of Thomas SCARFF and Eleanor KEWLEY becomes a good candidate for Lynda's James after all. My one concern is that there are no children of James & Margaret named after the parents. However, the IGI doesn't show any other James other than one in 1813 that would be too young. The IGI has missed some people, so we can't be sure without further work.

Thomas SCARFF bp 24 Oct 1762 Lonan, son of Philip SCARFF and Ann CALLISTER. He was buried 8 Feb 1839 Lonan age 76.
I think this is correct: Eleanor KEWLEY bp 11 Mar 1764 Lonan, daughter of Patrick KEWLEY and Margaret WATERSON. She is in the 1851 census widow age 90 born Lonan living with son William, a Coal Porter age 53 and family living at Water Lane in Douglas. There is a burial 2 Apr 1853 of Eleanor Scarff "From Douglas, buried at Lonan, aged 93". Based on baptism, she was only 89 but at that age who should quibble!

Children of Thomas and Eleanor, at Lonan:
1. Margaret 10 Jul 1788
2. Jane 9 May 1790
3. Anne 20 May 1792
4. Thomas 26 Dec 1794. Burial at Lonan 10 Oct 1851 of Douglas age 64 years. Episc will 1852. Issue.
5. William 29 Jan 1797. Marr Ann. Issue. In Douglas in 1851 census, and Onchan in 1871.
6. John 9 Feb 1800
7. James 23 Jan 1803
8. Isabella 25 Nov 1804
9. Isabella 15 Apr 1805 (these are very close together; perhaps the same).