Front license plate install?

Hi guys! I just received this vehicle from an aging family member and need to get a front license plate installed for the state that I live in. I’m scared that a dealership or shop would charge me a silly amount of money to do it, so I’m attempting to do it on my own. I was able to order a license plate bracket that matches the year and model and seems to fit correctly, but it didn’t come with any of the necessary hardware to attach it.
As far as I understand I need: the bolts to attach the bracket to the car (there are no holes drilled in the bumper)
The “j nuts” to correctly attach the license plate to the bracket
The assorted washers' screws and nuts

I’m having a hard time finding the j nuts specifically, but if I were able to buy all the hardware as a complete set that would be much preferred. Could you point me in the right direction?