Steve Blust is right when he says, "I would ship it in an airtite like the one pictured and a bubble mailer. It will cost $1.93 if you buy the postage through PayPal, and that includes free tracking. Insurance would be extra."

Let me add:
(1) instead of an airtite, for most chips I like to sandwich them between taped thick cardboard -- cheaper than an airtite and helps with the 3/4" thickness required for tracking.
(2) it depends on your feelings and situation (and if you need for peace of mind), but for most mailings under $100, I forgo the insurance and rely on the tracking for protection. Insurance is even a flag to steal the parcel. You are better off in the long run doing as I say. Plus, if the one in 500 times the parcel is lost or stolen, you don't have to fill out the time-consuming post office insurance claim form.

Robert
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Dan Dailey in publicity photo for "Meet Me In Las Vegas" (1956).
http://www.antiquegamblingchips.com/StillsB_OthMaleAcs.htm