Is this engine recoverable?

And why bother, when tor a little more, you coulda had a V8
That's more to bore n hone and more for heads and rod resizing. Added 2 more of everything AND now you need a transmission for a v8...sooner or later a rear end.. definitely better brakes if not disc., exh, ignition, mounts.etc
Kiss method. If it was somewhat appeasing to him as it is 'aside from the fouling ' a rebuilt 225 =compression, more air flow through non sunk valves etc.. it'll feel like twice the motor he has now.