Rolling Stones 'Trouble In Mind'

Can anyone shed any light on the track 'Trouble In Mind' which is a recently-bootlegged outtake from late 1966 - all I know is it's credited to Brian Jones and is a 12-bar instrumental featuring prominent boogie woogie piano (from Ian Stewart I presume), and two lead kazoos! They're all over the place, a bit like lengthy sax solos. It's hardly a lost classic but good fun to hear.
It's sourced from vinyl and the story I got was it's from an acetate - there's a bit of studio chat at the start - belonging to Chris Jagger. He played it on a radio show once, which is where the bootlegger took it from, but I don't know when.
I wonder if Mr Jagger has any similar goodies tucked away - it's amazing but previously uncirculated stuff is still coming to light eg. the Chess Studios outtakes of 'Reelin & Rockin' and 'Goodbye Girl' ('Get Back To the One You Love') which have appeared recently

 

Where do you find this stuff?

 

It's not "I Can't Be Satisfied", right?