From Trove newspapers - owners of Alhol Brae
1838 – George Bilton -2560 acres
1842 - John Kerr, Esq
1845 - WILLIAM GELLIBRAND
1846 - Thomas Lloyd Gellibrand
1853 – Mrs. Aitkin – 1640 acres
1856 James Lamberd
There is a range of genealogy sources related to Tasmania from here some of which are online.
It sounds like Charles Octavius Parsons, owned it in September 1837 but it's not clear whether he still owned it when he died in 1863.
Charles Octavius Parsons sold both Kimbolton Park and Athol Brae to George Bilton in August 1838.
Source: The True Colonist 31 August 1838