I don't mind cobbling one together with a Raspberry Pi & accessories, if that is possible. In fact, it might be a bonus if I can program it myself. But that isn't a requirement.
Otherwise, I am looking for a cheap, portable RFID reader with 2 to 3 metre range. Preferable passive tags, but I will take active if it somehow brings the price down.
A must have is a Bluetooh or WiFi interface to transmit the value just read, plus some storage in case it is out of range, so that it can store values read & transmit them when in range.
The more that I think of this, the more that I want to code it myself :-)
Cheap means sub $50, preferably cheaper. An IP67 housing is desirable.