have a look at http://www.isle-of-man.com/manxnotebook/tourism/pgrphrs/pgrhrs.htm to see if it helps date any (I would be happy to receive questions if you you find any names not in my list) - if you are on-Island then taking them along to a meeting of the IoMFHS would be a good idea (members workshops crop up about twice a year) - otherwise you need an indulgent website to host them!