I just completed my build.
This pressure cooker, mostly for volume and I didn't have a smaller/cheaper one on hand.
http://www.amazon.com/dp/B0000BYCFU/?tag=skimlinks_replacement-20
I didn't install the pressure gauge that came with it instead I used an existing keg pressure monitor that I picked up at LHBS, which uses a gas-out quick disconnect.
http://www.northernbrewer.com/shop/bleeder-valve.html
I re-used the keg post setup I have from this build:
http://www.homebrewfinds.com/2012/11/recirculating-draft-line-cleaning-build.html
Picked up a couple SS washers, 9/16" ID: 17/16" OD. Used an oring that goes around a keg post, and then a small 1/4" FPT coupler.
The put the washer on the bottom of the keg-post with threads, then the oring, then put that through the hole in the cooker lid. On the underside, I attach the coupler hand-tight. The washer on the outside pushes the oring for a tight seal.
Then I attach the keg pressure guage to the post in the lid and we're all good.
Final attachment looks like this.
I used 3/8" ID silicon hose, you have to push it over the check-valve threads, but it fits, then a clamp.
For the want, I picked up a 3/8" barb to 1/2" FTP, which threads onto a 1/2" PVC threaded elbow. Then a simple 2' x .5" PVC pipe, and a cap on the end. I drilled myriad holes near the bottom foot.
After attaching it all, built pressure up to about 12 psi, and then opened the valve. Steam flew out and I got a temp reading. During the out-flow of steam, pressure was around 5psi.
I'll likely replace the pvc with real pipe since post-test-run the pvc was hot enough to bend. I want to find easier pipe to work with than the normal gas pipes; I don't have the equipment to drill holes in those pipes.
Maybe some simple copper or conduit. Copper is pricey though.