Baikal makes youth model single shots. They are hammerless and are in .410 and 20 gauge. If you look at the specs, the weight is listed at 9 lbs. This is an error of translation from the Russian. My full sized adult version in 20 gauge weighs 5.4 lbs. Cheaperthandirt offers them and the costs run from $91-140. I haven't found another vendor. Shipping is either free or $11 to your FFL holder depending on which warehouse guns ship from. Baikal is marketed by USSG, Inc.
Mossberg makes several youth model pumps in .410 and 20 gauge. There is a mini series and a youth series. The guns come with sectioned stocks so the lop can be reduced or increased simply by unscrewing the pad and adding subtracting sections. The Super Bantam is one such model which comes with a certificate to buy at discount the adult stock once the child grows.
I taught a young boy shotgunning with an old Beretta gas operated auto. I handloaded 12 gauge rounds with 7/8 oz. loads. I cut the stock off and added the section back as he grew. Gil
