If original, that's got a 3800 top end, 1.880" diameter plain bore with a chrome plated piston & standard 1/16" think rings
Piiston/Rings/Cylinder are part numbers 5300-10626/25933/11957 respectively
Cylinder 11957 has been superceded to 12067
Still a very good saw for firewood, just not as desireable as the thin ring 3.7
I still can't understand Sears' logic in doing that...