Solved! For all those makers in the UK looking for rapid-setting concrete, specifically Cement-All, here is a solution.
"I am Mr Rapid Set in the UK, Cement All is in stock and the pharmacy range also, Set Control and Flow Control. All the Rapid Set range is manufactured in Germany so comes with full European approvals and CE Mark. Any customers you have please ask them to contact me direct, we are currently supplying quite a few Kitchen Counter Top companies."
-STM Ltd, UK
To inquire & order concrete in the UK, I have been advised you should personally contact Peter Bennett at STM.