johnwasser:
No. The 5V pin is not a digital output pin. It is part of the power supply.
IF the device draws less than 20mA you can power it from a digital output pin. For any higher current you will need to use a transistor.
Some chips have a reset input. Does the RFID board have a reset input?
Pin 7 on the reader is labelled: reset terminal, active low to repeat reading