Marion, your horse is silver buckskin. If he was buckskin his mane/tail would be
black or at least a dark chocolate. That's one of the identifying traits of buckskin...... the points, which includes mane/tail
must be black - many are faded to an off-black/dark chocolate, but they are still not as light as your colts. Actually your colt's color is about as "textbook" silver buckskin as you can get......
I looked at his pedigree on your website, thank you for having photos in his pedigree, it makes it so much easier!
He's getting his coloring from his dam, who is also a silver buckskin, I'm just guessing but the silver is probably coming through her sire (who is registered "buckskin" but is probably silver buckskin) from Lazy N Red Boy who's a silver bay. His sire is black, nothing coming from him except perhaps the black base coat, which also could come from the dam - your colt could be homozygous black.
So while your horse is a silver buckskin, you are probably not going to be able to register him as such because as far as I know, neither registry allows silver buckskin as a color. His dam who is silver buckskin and her sire who I'm betting is also silver buckskin are both registered as buckskin w/ AMHA. So they might allow that, or they might want to register him as "dun", which he is not but if the registry wants to register him that color there's not much that can be done about it.