Hi Blue Jacket,
I am researching the maritime history of the River Welland & Spalding, Lincolnshire. Most of the vessels from Spalding which came under the Port of Boston were registered at Boston. The Ships registers for Boston from 1827 to 1892 are at the Lincolnshire Archives with some on microfilm. The registers give vessels name, builder, type of vessel, measurement & tonnage, owner, & Master at measurement date. I expect most of the Sherringham vessels would have been registered at Yarmouth as I see from your picture the vessels reg is YH. Perhaps you can find some information from the Norfolk Archives or maybe they are still held at Yarmouth.
Good luck with you research.
Keith