It's not my speciality, but I suspected a typo here, and I think I was right. A convoy is a number of boats sailing together, often under escort, and it appears that this is a little-used word for the professional who takes a boat or boats from one place to another ie a boat-deliverer.

Sea and Boats-nautical directory, used boat sales-sea-convoyor_boats
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You are here.:: >> Home => Convoyor boats ... sailing convoying of boats and engines with or without skipper in the Atlantic, pacific, med, Indian Ocean ...
www.sea-and-boats.com/uk/convoyor_boats-49.htm

This link comes up with a site that explains the job, although it doesn't use this term:
http://www.yroryachts.com/

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Note added at 58 mins (2007-11-06 21:24:24 GMT)
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Re asker's note:

The word has its origins in the noun/verb convoy, but a convoyor, as stated above, is someone who delivers a single boat or boats.