Shouldn't be that hard to insure,surely. Maybe,to at least see if it's listed,use Hippo for guidance (I know they useless,but they list practically everything that 99% of insurance companies cover). If not, I can give you the number of a broker who is a petrol head and may be able to help.
Just checked on Hippo and there are plenty companies that cover the M Coupe. Using my details payments ranged from R350 a month to about R1000 a month.