You could look at infomaniak, but I didn't have the best experience trying out (or even getting started with) their services. Finding a provider that has all of Proton's apps is going to be tough (or at least it was from me while I was looking to escape from Tuta). Good luck, tho.
EDIT: Infomaniak is on F-Droid!
EDIT EDIT: Infomaniak is only available in Europe! Infomaniak is only available with a European phone number, so using a VPN won't help! ๐๐