I did a quick search on eBay and found these: https://www.ebay.com/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=harry+potter+bloomsbury+hardcover+set&_sacat=267&LH_TitleDesc=0&_sop=15&_osacat=267&_odkw=harry+potter+bloomsbury+hardcover
and on Amazon: https://toptalkedbooks.com/amzn/1408856786
You’re talking of the Hardback box set of the currently published ‘children’ editions - is this them: https://toptalkedbooks.com/amzn/1408856786
The ISBN for that entire box set is: 9781408856789
It is a beautiful set - I own it in both hardback and paperback - and you won’t be disappointed!
If so, you can order from Amazon.ca and ship to the US. Be sure to check that the seller you buy from is ‘ships from and sold by Amazon.ca’ also.
Also FYI - as you’re in the US, I may have an easier solution for you in terms of finding the UK Bloomsbury published editions of the books. Canada also sells the original Bloomsbury books - imported directly from the UK and distributed in Canada. If you’re ever looking to purchase a UK edition, simply order on Amazon.ca as they are generally cheaper than on the UK site, and shipping to the US from Canada is also much more affordable than from the UK. There used to be shipping restrictions to America for the UK editions and Amazon.ca would refuse to ship, due to distribution rights by Scholastic, but they are allowed to ship to the US now so that is an easy solution for you. Again, the UK books sold from Canadian retailers are indeed imported from Britain and are the Bloomsbury published versions.
And I know - I’m working on it - we were away on holidays for Canada Day but I will get a good picture taken of my collection for you as soon as I can. I have to do some rearranging to get them all in the shot as right now I have an entire room in my basement dedicated to them - a cool, windowless, dark room to prevent aging and discolouration of the books and/or pages.
Here you are my friend, ships to America: