I bought 2 13x6x5's from surplus center.. $5.50 EACH.. thats a pretty freaking good deal.. it almost cost as much for my rod ends they were like $4:50 each.. if i could i would make love to surplus center.
shipping would be about the same as if I bought the wheels from harbor freight (we have a local store). Plus I' m not finding anything as cheap as you did in that size.
http://www.surpluscenter.com/item.asp?item=1-2082&catname=wheels there the size i mentioned. ok its 49 cents more hahah.. shipping for my stuff which was 6 sprockets 2 tires 4 rod ends and some #40 chain was only about 20.. and these are MUCH better then anything you get at harbor freight the tires i got are kenda turf tires 4 ply...