I am currently dealing with replacing my rims, wich are confirmed widow makers (had one blow up on me one time, when i in ignorance toped off the air in the tires). Note: I now know you can not just air up Firstone RH-1 style rims AKA (Widowmakers) they must be pulled off the vehicle and placed in a tire cage before you air them up, or due any mantainence to them. Im luky i wasn't killed. I was just driving away after airing up when the left rear outer blew. The explosion was huge! The rim split completly in half at where the two halfs join. The outer half was blown approximitly 50 feet away, and probably would have gone further if it haden't been stoped by another veihicle. I looked at the picture you posted. It doesn't look like my rims. Yours appears to be a lock ring style. These are much safer than the RH-1. But they still are bias bly tube type tire/rim setups that must have respect. If you decide to keep what you have and not up grade to one piece rim/radial tires, be sure to have them serviced by a profesional tire shop that will have the tire cage. Or shop around and get your own tire cage. That way if the due pop, the cage will keep you from being killed.
