take a look at ford bronco II.

I drive a strada (truck pajero), and just picked up a double tube rear bumper for 40 bucks.

the frame distance is off by less than 1.5 inches. that allows me to box up the bumper bracket and add maybe 1/4" spacer, make new brackets to fit my frame holes and voila. bolt it to my frame and im happy.

of course i have yet to do all this, but it looks promising.

I could get pictures if you want. might help you out.