Price is £8 each (I have 5) plus whatever postage will be.
Standard International (to the US) is about £5 which I never actually use as I prefer to send by tracked/signed but as that would be almost £10 it may not be wanted. Standard covers up to £20 insurance (allegedly and which I didn't realise) so I am happy to send that way if preferred. I will obtain a proof of postage too.
I usually wrap in bubblewrap and put inside cardboard plus I use a padded envelope but will try a different way so it is possible to send as a large letter and not a small parcel. I've had a few sent that are set into cardboard as opposed to bubblewrapped so let's see how that goes.