where con I get parts for a 1976 suffolk colt petrol mower?

Try www.briggsbits - they seem to stock all kinds of parts for Briggs & Stratton engines.
For other lawnmower spares try "OldLawnmowers" - think thats right. I used them to find parts for a 1963 Colt cylinder mower and found them very useful. Apologies, I can't find the correct website name.

Mike Giles
April 2015