Actress Sophie Neville has lots of behind-the-scenes footage from the 1974 Swallows and Amazons film on her YouTube channel.

Several videos of Swallow from July 2011 are available on the Nancy Blackett Trusts's YouTube channel.

Trailer for the 2016 film in conjunction with the BBC (but not starring our 'Swallow'):

Swallow sails on the River Thames at Tamesis Club, summer 2011:

Swallow sails for the first time (April 2011), since filming ended (1973). With guest of honour Sophie Neville:
(skip a few minutes if you're not interested in speeches!)

Just after restoration, in pristine condition at the London Boat Show 2011:

Here is Swallow, as purchased in 2010, before restoration work began:

A clip from the 1974 film: