Shipyards and boat builders: sailing yachts/cabin boats

A company created in 1958, Pearson Yachts quickly became a high production builder of sailing yachts. At one time building a boat every day, types of fiberglass boats sold under the Pearson Yachts name ranged from the 12-foot Petrel to a 53-foot vessel. Controlled by Grumman Allied Industries since 1961, Pearson Yachts was sold to a private investment company in 1986 that would incorporate large powerboats in later years. Pearson Yachts history ended 1991 but the several brand names of the marine company would combine into another manufacturer.

William Garden was a naval architect and marine engineer: https://en.wikipedia.org/wiki/William_Garden

Founded by Ray Walsh and Len Wakefield as Thames Stuctural Plastics in 1959, originally to build fibergass components for a number of industries.
In 1962, the first sailing cruiser is launched (Snapdragon 23).
In 1981 Thames Marine ceases manufacturing. Distribution & marketing taken over by Maplin Marine who ceased trading after just 12 months.
No longer in business.