You can use Yubikeys in OTP mode with Duo applications that don’t show the browser-based Duo Prompt. If you purchase Yubikeys that support both U2F and OTP then the one device can be used with both types of auth in Duo. Learn more about our Yubikey OTP support here.
We also support OTP hardware tokens from other vendors like Gemalto and Vasco. Are you unable to have any third-party tokens shipped India?
RSA tokens use proprietary algorithms, so they can’t be imported into Duo.