Please give a reference - there was no significant boat building on the Island at that time - Peel had no real harbour (that came c. 1740 with the running trade), Douglas had no significant ship building and post 1710 to 1765 nearly all its income derived from the running trade (eg large Dutch vessels breaking loads and/or illicit imports) - Ramsey also had no ship building (see history of Ramsey by Constance Radcliffe).

Why would timber be imported several thousand miles when there was more than enough in the Baltic with a long established link by the mid 18th Century.