PEI bed are 20€, not 100€.
Just buy a compatible one on amazon or elsewhere.
You just need to have the bed size somewhat correct, and the magnetic base have a sticky surface that will adhere on whatever is below your glass bed (usually some metal structure to hold the glass)

Consider that a new power efficient CPU may be cheaper by consuming less electricity over a few years!

Where I live, for 45€ you get 800GB, not 8TB :').