Davison / Davidson stumped in Derry, Coleraine any help would be great

Hi,

  Myself along with other's in our family tree are stuck with information about Samuel Davison/Davidson (~1778-1863) 

Not sure who his parent are and when he migrated to UK, looks to have married and started a family in Tolpuddle Dorset ~1813

Married Diana Balston 

Not sure if the same Samuel Davidson who had a military service in the 7th Battery in West Indies (attached records) the age doesn't quite match but birth place does.

Any help would be appreciated.