Over last few days I've been looking at Arbory Wills to see what can be extracted from wills & decrees (Arbory burials are missing pre 1729) - a first attempt is at http://www.isle-of-man.com/manxnotebook/famhist/pregs/aybu1701.htm which summarises some 100+ wills/decrees of that period.

There is also a list of defuncts from other parishes (courtesy of Manx Museum) that do not appear to have a will in period pre 1700 - see http://www.isle-of-man.com/manxnotebook/famhist/pregs/defuncts.htm