Hi Tanya and welcome. If you have the standard "Carbine Length" Handguard AM-15, a direct replacement quad-rail handguard is here: budsgunshop.com/product_info.php/products_id/37315/utg+pro+pro+quad+rail+carbine+ar-15+black+hardcoat+anodized+aluminum+picatinny ------------ Just let us know your specific model for more options if needed. cheers and stay safe!

Hi Tanya, it's hard to give an accurate answer without know the exact AM-15 model. Some have A2 Front sight posts, others do not, some have free floating handguards.
If you have the A2 front sight post with the clamshell type handguard, a drop in handguard will work, like these >>> mountsplus.com/handguard-for-a2-front-sight.html
.
https://rockfiresportsinc.com/product/ar15-m-lok-drop-in-handguard-carbine-extended/
.
Stay safe & have a great day!