bios file .bin for lenovo thinkpad t8

Hello,
i am searching for a bios file .bin suitable to be written to the bios chip winbond W25Q64FWIG of my tablet Lenovo Thinkpad t8.
Do you have a suggestion, where can i find it?
I downloaded the old corrupted bios file reading the chip by a ch341 programmer, but i am not able to fix this file.
I need a new correct .bin file suitable for my tablet, and if possible i need to know how to recover the sn, mac address, etc from the old bios file and write this information on the new bios.
I am a newbie, perhaps someone can help me?
I can pay something for the new bios, if needed.
Let me know,
thank you!
Lodovico