I think that the strutted glider is a Slingsby T31.
And the yellow glider at 1:46 - possibly a Slingsby Swallow. I got my Silver Height in one when a member of the Southdown Gliding Club - the bargraph shows a vertical line from where I got the thermal at 800' and left it at 7500'.
I've got a lot of happy memories of gliding in the 70s