Having spent a lot of time recently looking for a replacement for my Sony PRS-T1 there are three other sites that are worth a look:
Cybook Muse:
http://www.bookeen.com/en/
ImCoSys:
https://www.imcoshop.ch/
Onyx BOOX:
https://onyx-boox.com/
If memory serves, they all have models with physical page turn buttons on either side of the screen.
I ended up buying a Sony PRS-T3 & a Pocketbook Touch Lux 2 (used but very good price). Initially I found the front light made the Pocketbook very difficult to read on, but the more I use it the easier it is becoming.