Dually Suburban.

[Colt Cobra]

apparently, the white and silver Dually burb that is pictured on the 1st page is for sale, minus the roof rack

[BigBlocksRule]

If you go with factory fenders, you'll need to make sure to get the spacer that fills the gap in the fender after you cut it, otherwise you'll fill the space with crap and everything will rust out within a couple of years.
I bought a couple of 1-ton crewcabs to part out this year, one had perfect dually fenders. I used a sawzall and cut about 1" away from the dually fenders all the way around, it was easier than trying to remove them as it sat, plus I got the spacers plus the bolts, etc.
I've bought a couple of dually beds in the past few years, they generally go for around $500 with good fenders. I had one pair with a few cracks and dings, took 'em to my local shop (Hills HotRods) and had the glass guy repair 'em and run an extra bead of fiberglass around the openings where they generally crack. Make sure you put some type of liner in the top inside of the fender to stop the stars and cracks from gravel, it'll sure screw up a good paint job...