When last did you check how secure your jack and spanners etc. is in its holder... and I probably should have asked this first, is the rattle inside or outside.....
Adrian, I'm not sure exactly which clips you need , but at Jacqueline Mall there is Bracken Motor Spares, speak to Marvin ( tell him Cedric sent you ). I know I saw some of those black plastic clip things there.
There is also a place in Boksburg that stocks the rubbers ( door rubbers, window rubbers etc. ) that also apparently stocks those clip thingy's