Hi everyone and especially you Sally and I didn't want to be the one to have to post this on here but ................... !!!!!!!
I know I said at beginning your idea for Michael's birthday was wonderful but, at same time, had a little niggle that your idea might not work. I looked up Post Office details on Internet and started to believe my misgivings were correct. I then sent an e-mail to Post Office and yesterday was in my local PO; from them and from answer I have now received, today, from Royal Mail, your idea is not workable outside the USA. You cannot send mail, from one country to another, with any other postage but the country of origin on it, therefore, for anyone to send you, Sally, a SAE with their country's postage on it will not work as, when you attempt to post it back, USA postage service will not recognise the stamps used. Here is reply I have received from Royal Mail and because of, only way I can see your idea working Sally, is for those who want to send Michael a "birthday card" in your "birthday box", is for them to buy one of the relevant size and send it directly to you. No use you supplying the cards, except for within the USA, for only way that would work is for you to pay postage.
Sorry to write such a downer post on such a wonderful idea but looks as though has to be re-thought.
Sylvia Your wee Scottish friend
Enquiry Reference # 171120-002147
Response By E-mail (Anthony) (24/11/2017 10.31 AM)
Dear Miss Doughty
Thank you for contacting Royal Mail.
I'm sorry, UK postal stamps are not valid for postage with the United States Postal Service.
You can send an SAE but the postage would have to be paid by the sender in the USA.
You can send ‘pre-paid’ item’s overseas if you have an International Response Licence (mainly used by business customers). Further information on this service can be found via the link below:
I am sorry my reply could not be more favourable, if I can be of any further help please get get in touch.
Customer Service Advisor