Tony, you’re in luck, I just found all of the info about the inner tubes.
I was researching them about 18 months ago because I needed 9 of them for my M1003. I asked the question on Steel Soldiers, pretty much just “Where can I get them? And how much will I pay?” Well, I got a lot of replies and a couple of guys said they were available for $30 each. I followed the leads but it turned out that not a single one of them was accurate!
Okay, let me cut a long story short:
I found them locally at a company called Purcell Tire Company in Pflugerville (near Austin) Texas. They cost me $59.95 each plus 8.25% tax.
They come 3 in a box and Purcell would only order multiples of 3 for me.
Here is the info on the side of the box:
Trans American Rubber
1-800-922-8823
Englewood Co 80110 USA
www.transamericanrubber.com
Part #: 3R55
Size: 16/1800R20
Valve: TR179A
QTY: 3
C/No: TRA-45F
Okay, that’s all. I tried being sneaky and calling the 1-800 number to see if I could get them cheaper by ordering directly from them. No dice. They only sell to retailers with a tax ID number. Oh well, I tried.
Given the above info, any good truck tire company should be able to get them for you. Once again, you might have to purchase a full box of 3.
Take a look at their website to make sure that the valve, TR179A, is correct for your application. The valve a few inches long and makes a sharp 90 degree bend about 1 inch from the tube.
Okay, that should be enough info to get you started. Obviously, Purcell Tire Company charged me enough money to cover the shipping and make a profit, so the $130 that you were quoted seems a bit greedy. Unless the guy is selling a much better inner tube. Mine are very robust.
I’m starting to blather now so I’ll quit.
-Sarge