Thought this might be of interest:
Kindle Deals for Christians - Tim Challies
"This is a curated list of hand-picked Kindle deals that are of special interest to Christian readers. I update this page on a daily basis as new deals become available."
https://www.challies.com/kindle-deals-for-christians/
Tim Challies is a pastor at Grace Fellowship Church in Toronto, Ontario, a blogger, an author, and book reviewer and a co-founder of Cruciform Press.
a few recent examples:
God's Love: How the Infinite God Cares for His Children (Classic Theology)
Kindle edition by R. C. Sproul
$0.99 US
https://www.amazon.com/Gods-Love-Inf.../dp/B008VBPXDO
The John MacArthur Collection Volume 1: Alone with God, Standing Strong, Anxious for Nothing, The Silent Shepherd
Kindle edition by Jr., John MacArthur
$0.99 US
https://www.amazon.com/John-MacArthu.../dp/B018RSXO9A
CSB Worldview Study Bible
Kindle edition by CSB Bibles by Holman
$2.99 US
https://www.amazon.com/Worldview-Stu.../dp/B07CYQDFXL
$3.73 CDN
https://www.amazon.ca/Worldview-Stud.../dp/B07CYQDFXL
Forensic Faith: A Homicide Detective Makes the Case for a More Reasonable, Evidential Christian Faith
Kindle edition by J. Warner Wallace
$0.79 US
https://www.amazon.com/Forensic-Fait.../dp/B06XWLZBXS