Suffolk Punch / Qualcast Cylinder Petrol Cylinder Self Propelled Roller Mower

Qualcast Suffolk Punch Self propelled cylinder petrol motor mower. Believed to be circa 1962-63 Shed find.... runs well and has recently cut my lawn well. Could do with a bit of titivation. I am not an expert on these but I believe the pull start and fuel tap are not original (made of plastic). Known Faults: A threaded stud has pulled on the pull start and a sheild on top (spark plug cover??) is broken, the fuel tap leaks and the inside of the fuel tank is pretty rusty. Oh, there is no grass collection bucket either.