The guy I used last time charges £110-165 for a Class II (depending on what you need).
Have no idea if this is more, or less, that you pay.
I did my last (Class 1) with him - no complaints:
Mach Med | Aviation Medicals
OC619
Mods: If the link breaks some rule, or other, then please remove it. I, honestly, have no connection with the business - beyond having my medicals there.