You can ship it USPS where you don’t have to disclose the contents (as it’s not a ‘firearm’ according to the ATF and fully legal to ship to a residential address) or you can disassemble it and ship via UPS, where you do have to tell them it’s Black Powder gun parts. You can ship it with UPS assembled but it can’t go Air Mail. You also have to ship from a Hub shipping UPS. State law applies. I think Jersey may have to go to a FFL but most don’t.. Double check.