Hohenbuehelia have cystidia. That species has metuloid gill cystidia which would be quite fun to look at. I’d also check the iodine reaction of the spores.
Clitocybe gibba would be my first thought (Clitocybe lack cystidia)
Thanks Adam, yes I will need to start getting to grips with microscoping features beyond spores, alas no gill specimen here. I was put off Clitocybe gibba on account of how thin the flesh of this specimen was. Thanks for the input and I will add iodine to my growing collection of chemicals.