Several titles in the historical mystery series featuring Kate Haywood and the young Princess Elizabeth have dropped in price at both Kindle US and UK. To make it easy for any moderator who may not be familiar with this series, all five of the titles were originally traditionally published - you can just click on the "mass market paperback" version to verify. I've also read and enjoyed several titles in this series.
If you want to get a "regular" link, rather than the Smile link, just replace "smile" in the URL with "www".
Murder at Westminster Abbey, #2, $0.99/£0.77
Kindle US/Smile:
https://smile.amazon.com/dp/B07CCKMDPQ
Kindle UK/Smile:
https://smile.amazon.co.uk/dp/B07CCKMDPQ
Murder at Whitehall, #4, $0.99/£0.77
Kindle US/Smile:
https://smile.amazon.com/Murder-Whit...dp/B07C6RBX9C/
Kindle UK/Smile:
https://smile.amazon.co.uk/Murder-Wh...dp/B07C6RBX9C/
Murder at Fontainebleau, #5, $0.99/£0.77
Kindle US/Smile:
https://smile.amazon.com/dp/B07C6L1DXH
Kindle UK/Smile:
https://smile.amazon.co.uk/dp/B07C6L1DXH
Murder at the Queen's Masquerade (novella), $0.99/£0.77
Kindle US/Smile:
https://smile.amazon.com/dp/B07CCJ7F5J
Kindle UK/Smile:
https://smile.amazon.co.uk/dp/B07CCJ7F5J