I see no pictures!!
However there certainly was an Atco Toughcut which was around with various engines up until the early 70s I think. The chassis had many parts in common with the Atco SF34 and SF35 Mini gang mowers. Your version with the Villiers Lightweight was designated The Atco 20″ H.D. Sidewheel Motor Mower. Other variations were, the SF33 with a BSA/Villiers Sloper engine, SF13 with a Villiers Mk7 and the 24″ SH6 with a Villiers mk10. There may well have been others!!