Good morning!
I'm an electronics/software engineer with 10 years expirience in RFID systems (ISO15693 - incl. long range devices and ISO14443 ) and more than 10 year expirience in C/C++ programming.
My last project based on Raspberry Pi was a "hands free" ski resort turnstile (Functions: reading and writing data on tag - >50cm range, gate control, height sensor, 2D animated graphic, TCP/IP, SQLite local database).
Load of devices(ski resort gates) that I worked on is thousands of use per day and they work 24/7.
For Your project I will use Raspbian and SDL library for 2D graphic (without X server -I think there is no sense to start X in Your application), which I have tested and which works for my customer in professional devices. I can give You help with configuring Raspberry Pi for 24/7 use (r/o partition for the system; r-w for variable data, etc.).
We can discuss the best solution for You that depends on other factors like load of the system, environment of use the device, etc.
I can get You VAT UE invoice.
I just started my adventure with freelancer.com as my account says...
Best regards
Wojciech Bogal