I picked up the bumpers locally from another Mud member, I wasn't really in the market (yet) but he made me a deal I couldn't pass up. They are both ARB, the front is for the HD models and doesn't bolt straight up, the frame is too short. The plan is to extend the front of the frame by about 3.5", which should give ample room to add a couple of extra bolt holes to the bumper. The rear is an odd one, I have only been able to find a couple of photos of it online and haven't been able to look it up in any of ARB's worldwide catalogues. I really like how it looks though.
It took a while to track down that number when I ordered it. I ended up calling arb directly to get it. They had us stock at the time (2018) when I ordered it. The number is 5612010. It's not listed anywhere in the catalog. But if you take it to an arb dealer they should be able to order it.