I just used the system disk for a worst case test.
I found these contacts for Mtron SSDs in Europe:
Belgium:
http://www.ssdisk.eu/
Germany:
http://www.winkom.eu/
On www.ssdisk.eu you can find prices of 950 Euros for 32 GB and 1510 Euros for 64 GB.
My decision is made. I will get one of those.