IML: Wheel Rims

[ChiPieAlandPaula@xxxxxxx]

Hello All,
 I need some information from the "Mechanical gurus" in the club. I have a 64 Imperial. I recently had a set of 4 235x75x15 WSW radials installed. One of  the tires  that I replaced had an inner tube! The tire shop told me that the three other rims seem to be of the tubeless type. They based this on the fact that these tires all held air without inner tubes. To make a long story short, the forth rim is either bent or cracked. The tire will not hold air for more than three days. I told the tire shop to find a replacement rim. Of course, this is rather difficult in Montana. My questions are as follows: are these indeed tubeless rims? Is there a modern replacement for this rim? I am thinking of truck rims? If this is not feasible, who can I turn to for an original ?
                                                                     Allan from Billings, Montana