You can buy the Jayco Carry-Out Stove from your favorite Jayco dealer parts dept. I'll see if I can dig up the part number...
But, the problem that we encountered was the height of the outside rail on our new 16XRB was higher than the rail on our old pop-up.
So, I've cobbled together an outside stove and am almost done. All I have left is to fabricate the support leg and mount the factory support bracket to the bottom of the stove. Pictures coming soon. You can pretty much use any low-pressure drop-in RV cooktop and a quick-connect hose. Keep an eye on my "Mods" thread for more details coming soon.