For my money, up to 20" is perfect 359-2159-262 territory.
Not sure how common the '59's are to find in Jolly old England, but it might be hard to get one delivered to your door at the moment anyhow- so you have time to look.
They are a very easy platform to work on, just watch the age and check to see if the intake manifold attaches to the cylinder with a plastic clip (not good) or metal one (good).
Parts are easily available and Meteor make good cylinder/piston kits.
For me, the 372 would be great- but you have access to the 385 and I feel there is not a big enough gap between the two to justify having both until you become a compulsive hoarder of old saws like the rest of us here!