been there etc etc
shipped a Bullit frame fm Vancouver to Colorado... UPS. Raped me for $160 CAD (international shipping costs air) and it took about a week, not overnight.
When it arrived, I hadn't put a contents label on it declaring is to be US made, so the poor recipient had to pay another $38 USD duty.
IMHO find a way to ship ground,,. insured, and mark clearly what is inside, and the value. You need a proper label from any post office to do that..
Jim