Dynamically setting address of HT12E with Raspberry Pi
You can use the GPIO pins on the Pi to set the address and the data to send.

The HT12E uses 8 address and 4 address/data pins to select the address and data.  You'll need 12 GPIO pins from the Pi to drive the data and address pins.  The Pi has 25 GPIO pins, so that's covered.

The Pi operates on 3.3V.  If you power the HT12E from 3.3V, then you'll have no problems with digital signal levels.

You'll need an additional GPIO pin to drive the /TE pin (transmit enable.)

Entirely possible with a standard Pi and a bit of software.