where to find komatsu split rim 17.5/25

I have three rims that are split on my 02 wa180-3mc, and one drop centre wheel.

I have 4 snow tires that I wanted to mount this fall, however I have one rim that is not a split. I could not take it off.
the tire was too cold and too stiff to get it to come over the edge.. So right now I have the two snow tires on the front and my rock tires on the rear. I thought two and two is better than three and one.
does anyone know of a reasonably priced second hand split rim.