I remember Big Bear very well, the bands connected to the label used to appear together for mini festival events called Big Bear Follies (sometimes spelled Ffollies) - some great music!
There is quite a lot of information on the Web about the label and artists and Jim Simpson himself, he was a musician himself originally, played the trumpet.
This from Birmingham's Flat Pack Festival
In June 1968 a new night championing ‘progressive music’ took over the room above the Crown pub on Station Street.
flatpackfestival.org.uk