Boosting power transmitted by 433MHz module from 5v to 12v
The supplier of that transmitter/receiver set has let you down.  There is no useful documentation that would allow you to figure the power consumption.  You will have to guess how much current it will draw.
Specific recommendations for a product aren't allowed here - nobody is going to say "buy model X power supply from supplier Y."
Looks like your highest rate is around 2.5kHz, so you should be fine as far as speed is concerned with the level shifter.


I'd just go with a 12Volt wall wart that provides 1A.  It is probably too much, but it won't cost much more than a power supply rated for a lower current.  Once you have it running, you can measure the current draw and see how much it really is and maybe switch to a smaller power supply.

Do you have antennas on the transmitter and receiver?  It might help to experiment with the length and placement of the wire.

Just connect the negative lead of the power supply to the ground on the transmitter and to the ground on the arduino.