There are a few more seats available not listed here.
bicycle seats have a 7/8″=22mm clamp seat poles are 24-35mm w/22mm top end
4904 beach cruiser seat single w/springs $20 fits any moped with a bicycle-style seat pole
36098 seat single deluxe XL with/springs $40 any moped with a bicycle-style seat pole
seat single Peugeot new with 1″ post $45 fits Peugeot 103 and others with 1″ hole