I bought a brand new rim off of ebay
https://www.ebay.com/itm/ACCURIDE-29...72.m2749.l2649 $191 shipped and a tire For $138 with FET
https://simpletire.com/catalog/product/40966
Purchased the Roadmaster spare carrier for $522
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
We went to Alaska in 2013 but not in our Class A, we had bough a class C that had 17" wheels but never needed our spare, the key is drive at a reasonable speed for conditions. Top of the World highway is all gravel but some of it is smoother than the blacktop in alaska. Seeing how some people driver on the TOTW highway I am not surprised they have flats. Multiple times we had to pull over because some idiot would be barreling towards us at 70 mile an hour kicking up a dust cloud you would never find your way through.
Remember the 19.5 is not a common tire like a 15,16,or 17". I carried a patch kit and air compressor.