RE: Need 4 cycle valves
I have a ton of engines apart right now, these are the closest.
OS FS-91 Intake valve is 26.2mm(1.031" ) tall, 3mm(.118" ) stem, and 11.2mm(.441" ) face.
OS FS120 exhaust valve is 32.6mm(1.283" ) tall, 3.5mm(.138" ) stem, and 12.2mm(.480" ) face. The intake valve has a 14.2mm(.559" ) face.
Good luck.