Does anyone know

I would buy more of my books via a link to Amazon on AllaboutRomance (AAR).  My problem is; I live in Canada but my Kindle account is with .com. When clicking on the link in AAR reviews, I am instructed to update my Kindle to use the .ca account (I do purchase other items at Amazon and do use .ca frequently). While I am assured that I will lose no books and that I will have continued access to books purchased prior to switching to .ca, it is something I do not wish to do.  Often books are faster available via .com and I believe – although I have not looked into it lately – the selection is better at .com. 

I have not tried it here on Booklikes about I assume it's the same. Does anyone know what to do about it? Thanks.