Definitely ship via USPS.
He may be charged 12% sales tax on declared value plus a handling fee, $15 or so, Also, there's a chance there could be duty on it as Swarovski is made in Austria which doesn't qualify for the duty free exemption under NAFTA.
He may also get charged nothing, about 50% of the items seem to slip through Customs without being assessed. However, this is a high priced item, so chances are slim if you declare actual value.
