I'd not worry too soon here in the US. A rough outline of what it takes to get parcels to this side of the water when one is not using expensive airmail services.
10/18: Parcels are tendered to CH post for transportation.
1 - 7 days to load in at Container Freight Station (CFS) in Zurich as most likely freight center for co-loading in 40' ocean container with other US bound cargo.
2-3 Day transit to Bermerhaven or Rotterdam depending on the routing.
1-3 days at port Container Yard (CY) waiting load on vessel.
11-16 days: Ocean transit time to New York.
1-3 days to pull container from destination CY to bonded CFS for deconsolidation.
THEN the lot is customs cleared and tendered to the US Postal Service and enters the normal postal stream.
A very generous offer (something for nothing) from Les Nez with what I have heard are more like small decants (4 ml) than dinky samples. I'm not going to sweat this one for another couple of weeks at least.