For working in live TV, I have a 7 inch and 10 inch IPS monitor that I can put on the camera just above the lens.Your prompter op will probably come with only the equipment to send you a CVBS signal with the prompter lines OR send an SD-SDI signal.
I did a job with Kristen Bell a few months ago, and was told about wearing a prompter in advance, and would be a long walk and talk. I used a wireless HD transmitter/receiver (IDX CW-3) and wore the RX while handing the TX to the prompter op. On my rig, I also wore a Decimator 2 to convert the SD-SDI signal to CVBS, and sent that signal into my prompter. Boom, wireless teleprompter. I had to do a similar thing a few years ago for a special show for FOX.
Prompter ops generally don't have the equipment to send HD-SDI signals, just SD-SDI and CVBS. The prompter folks I had on the FOX gig were very nice, but not very technically knowledgeable about the signal coming from their system, and insisted they were sending an HD signal. After a couple frustrations, we got it working, but I basically had to get it running without their assistance, and you'll probably be in the same position.
If you're trying to make it wireless, you'll either need a standard def transmitter for CVBS signals (CanaTrans, Modulus, Boxx Meridian) or a digital transmitter that handles HD or SD over SDI (Teradek, IDX Camwaves, Boxx Meridian, etc). If you don't have a wireless system to rent to your production, they can grab one from the rental house specifically for prompter signal.