Reckon 4-core alarm cable would do it. Probably get it from B&Q
https://www.amazon.co.uk/Cable-Core-Burglar-Security-System-metres-Black/dp/B005EHY514/ref=mp_s_a_1_1?dchild=1&keywords=4-core+alarm+cable&qid=1592672522&sprefix=4-core+&sr=8-1
Thank you. I'll give it a try.
@Stevethecoffee started
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Reckon 4-core alarm cable would do it. Probably get it from B&Q
https://www.amazon.co.uk/Cable-Core-Burglar-Security-System-metres-Black/dp/B005EHY514/ref=mp_s_a_1_1?dchild=1&keywords=4-core+alarm+cable&qid=1592672522&sprefix=4-core+&sr=8-1