Yes it will work and yes you can do it on the cheap, Look on Homebrewfinds they have links to the parts you need. If you don't want the PRV, can replace the tee in their build with a coupler.
Having the PRV would be nice in cases where you over carbonated. You can set the PRV to open at a given pressure and let it be for a day or two.
Some shops sell these as well. I know Williams does.