Hi William and welcome. The Super Bantum would likely be best. The Youth models use a 13-inch (33 cm) LOP stock and a forend that sits further back than the standard model. The Super Bantam stock includes two recoil pads and a stock spacer. By using the short pad, the LOP can be reduced to 12 inches (30 cm); with the spacer and longer pad, the LOP is 13 inches (330 mm). Cheers and stay safe!

It would depend on his size however I would recommend semi auto to reduce recoil (Youth pumps kick like crazy) check out this tristar my grandson shoots a tristar semi and it has been great we started with me giving him 1 shell at a time to use it as a single shot budsgunshop.com/product_info.php/products_id/57212/tri-star+sporting+arms+20+ga+youth+24+barrel+w+2+extension+black+syntheti this Blue sporting clays gun is the one he shoots budsgunshop.com/product_info.php/products_id/118688/tri-star+sporting+arms+viper+g2+sr+youth+sprt+20+26+blu