I've no problem at all with you getting another device, but just to play devil's advocate, and maybe to save you some money:
Originally Posted by carrie5012
I source my books both from Amazon and elsewhere and use calibre for conversion with a pluggin to remove DRM so that I can store them for later use
If you're doing this, then you're protected from your concern that Amazon may close your account, which (as pointed out above) is extremely unlikely.
Is the mild annoyance of having to switch off wifi after sideloading your books really enough to justify buying a whole new reader and, probably, go through the process of converting your book collection?