Ransomes Marquis no spark

Hi, me again!

I’ve had the mower running perfectly until recently when it completely stopped running. Traced the issue down to no spark so followed the steps and found there was nothing coming from the internals. 
 

I therefore took this off and had it tested and each component was working so thoroughly cleaned the points and refitted, gapped correctly but still no spark. Has anyone got any suggestions as where to look next as I’m completely out of ideas. For reference it’s a sloper engine.

Thanks Josh