Hi S'cuder
For a so tiny and lightweight item, a padded envelop will be perfect. And Claydart will be able to send it as a letter, not a parcel.
This way, I think that he won't have to fill any US export form. The envelop will probably escape from import and custom taxes.
With USPS priority (and also first class mail), I've never got any trouble, and shipping won't be expensive
Generally, a letter takes 4 or 5 days to arrive in France.