Yes, the NSW Police had some. To quote Pedr Davis from Spotlight on Mini Minor Down Under "NSW Gendarmerie will get specially tuned versions of the Clubman GT - top model in the 4 car range - for pursuit work plus the regular Mini Clubman for station work". Info is hard to find, but I believe the mods were 2x1-1/2" SU's, 731 cam. He does not say whether they actually took possession of the cars, so may well have ordered then cancelled as the 'big 6's and 8's' were beginning to appear on the market.
The car was homologated for Bathurst Late 71/early 72 cars (minimum 200 built to race spec). The cars originally used the left over bits from the ceased production of the MkII Cooper S, including the powerplants which had the 9F/Xe/Y engines (stamped on block), although officially it was the 'new' engine number system used (here in NZ anyway!)- 120x/xxxx. My orange resto car has this. In other words - full Cooper S spec, inc motor. As the motors were used up, they moved to a 'standard' 1275 block which had the 120x/xxxx number stamped on. These blocks do not have the engine side covers of the S motor. This is the only difference as all the internals etc. were S spec. I believe that all late 72 and 73 cars will have the 'non S block' - check yours for absence of side covers.
As I said before, information is pretty hard to find on these cars but I'm pretty sure that the Bathurst cars had the 'genuine' S motors in them, seats without headrests and the ignition switch in the centre panel, same as a round nose as one of my previous GT's was like this (wish I knew then what I know now!!!). Leyland then introduced head restraints due to legislation passed.
Your engine number of 1206/1181 is a GT motor. Check also for the numbers stamped into the radiator cowl and the body number on the firewall. I've updated the pic of my orange car which now clearly shows this stamp.
See
http://homepages.ihug.co.nz/~gavin.agnew/resto1.html for pic.
Hope this helps.
Gavin