I have one mirror glass to offer which I don’t have a use for anymore.

Model: Pilkington Mirropane ChromeSpy 4mm
Size: 500 x 500 mm
Transmission: 8%
Reflection: 48%

It cost me 82€, I’d sell it for 60 € + shipping.
I live in Germany close to Duisburg so pickup is of course possible as well.
Let me know if you’re interested.

Thanks!