I know the feeling of finding decent usable 16" wheels, I started looking for some to use on my 51 F1 and unfortunatly somewhat like the ones shown above they sometimes look great on the outside but once you dismount the old tires you find that there isn't much steel left on the inside
and or they are not very true, I'm not sure how much out of true would be acceptable for a spare but I've got a couple different wheels that would work for you some 4" and some 4.5" wheels. in varying condition, but not very close to you. I'm in Salt Lake. let me know if you don't find something close by
Josh