And now I went to check out Georgette Heyer titles in the UK, and discovered a couple of handfuls worth (13 to be precise) of books currently priced between £0.99 and £1.99 there. Of these, a few were published before 1925, and should be public domain (PD) in the US, and therefore in most places, I think: The Black Moth, Instead of the Thorn, and Simon the Coldheart. Additionally, These Old Shades was published in 1926, and should go PD next year, even in the US, if you’re patient. And a few more of these are earlier titles of Heyer’s and may already be PD in countries that have shorter copyright laws, so YMMV…check before you buy if you are lucky enough to live in/visit one of those places!
Other than that, here’s the list, all at £1.99, except April Lady, which is £0.99
Lady of Quality
An Infamous Army
Pistols for Two (short stories)
My Lord John
link for them all at Kindle UK