You can order any muzzleloader via mail, or the internet anywhere in NY (other than maybe the "City of"). I just ordered my Omega from NatchezSS and it arrived without incident.
I live in WNY and have made the trek to Buffalo Gun to buy guns when I was a Deputy. Great gun shop...BTW!

Some stores like Cabela's, or others, might have issues or "self-imposed" rules regarding such, but there is no law that prohibits such.

Take care,
Bob