It is a Kaymar. They have never sold one to hold two spares in the states, but Man-a-Fre can order the swing arms from Kaymar. They are different than the standard carrier because they suspend the tire and wheel further toward the outside of the vehicle. From a recent email with Kaymar:
that's funny... I have a Kaymar without spindles welded- when I called MAF to get some new spindles to convet mine, they told me I couldn't get them here and I was on my own. I even sent an e-mail to kaymar in OZ, and they forwarded it to MAF.... I'll have to fab my own with someone else's spindles..
I'm thinking of possibly going double swingout with a removeable mount so that I can have either two spares, or one spare and one jerry can swingout.
2BADFJS will custom make what you want, im guessing that shouldnt be too crazy to build.
you can always PM him or check at his stuff at SROR.
The bumper you posted has aluminum on the top face and trailer hitch as well as extra lights, which i guess are kind of needed if you get 2 tires on there. Are these also what your looking for in a bumper?