Though Safepal has never open-sourced their software, they are planning to do so in the near future but the backing from Binance is one of the biggest selling point for them. On the other hand, the first wallet which you have purchased (Trezor) is completely open source including it's hardware and software which allows us to verify the code rather than trusting the makers blindly in storing our assets.

Since you are unable to find an official reseller for Trezor/Ledger in your country yet, it is always better to purchase them straight from the official website instead of trusting Amazon where the fake sellers deliver us with malicious products which can be risky for storing larger amount of funds. With regards to storing the seedphrase, one viable solution for storing them safely is to engrave them in simple metal washers and to load them onto a screw and locking them with a nut at the bottom.

@fillippone has written a great detailed thread on Securing Your Seed Phrase with Washers and it has helped really a lot of people in storing the seeds safely in a secure location. You can purchase a Blockmit Jig from cryptocloaks for $8 instead of 3D printing them on your own as well. The maximum cost for creating such a secure way of seed storing would cost no more than $25 for you and probably you can reuse the Jigs and Metal stamps for recreating your seeds indefinitely.