If you bring in $5000 worth of goods you will have to contract the services of a broker. I typically do this as I never have any problems entering the US, but often packages are held up when shipped. The broker charges a flat fee (typically) and any custom charges. The duty on the pearls will be 0, which is nice, unless you string the pearls in China. Finished jewelry is dutiable at 5.5%, whereas loose hanks have no duty. I hand carry every time because I import legally and have no custom issues - it also gives me a better peace of mind. If you fly back business class you do not have the same baggage restrictions, so you can actually carry a lot of stock.
One thing that I strongly, strongly recommend is to import 100% legally! As many of you know I was employed with an airline years ago. I have heard/seen many horror stories of crew members who attempted to bring things in without claiming them. While this may work for a while, you eventually will get caught, and have a target on your back for the rest of your life - not to mention the fines you will have to initially pay. One person in particular was caught with nearly $50,000 worth of goods, had her accounts examined, and was charged duty and fines on the last 2 years of purchases (that they determined she made in China).