No reliable one exists. Any site claiming "daily updates" is likely a scam or honeypot.
If you encounter a password-protected archive on Upstore, the password is almost always provided on the same page where you got the download link. Look for a line like: "Password: www.example.com" or "Unlock key: 123" . Never download "password finder" tools—they are scams. upstore password
"I tried 20 different Upstore passwords from a Telegram bot. None worked. One asked me to download an APK. Almost installed a virus." – u/throwaway_down No reliable one exists