I'm about 95% certain American Metalcraft's 8000 series tin-plated steel pans are the best pans for Malnati's style deep dish, although I've never had a chance to use them. Here are the model numbers for those pans, with links to a vending source for each of the standard sizes of these pans:
T800615 (6" diameter, 1.5" deep)
T800915 (9" diameter, 1.5" deep)
T801215 (12" diameter, 1.5" deep)
T80142 (14" diameter, 2" deep)
I also like the American Metalcraft N9494 pan gripper, even though I don't have one. (I used a similar pan gripper when I worked at Pizza Hut years ago, and it worked really well to grab their pans, which have the same form/shape as these deep dish pans.)
It appears that KaTom is also a good source for all this stuff, and KaTom may have lower prices than eTundra (T800615, T800915, T801215, T80142, N9494 pan gripper). However, do not interpret this as an endorsement for either site, because I have never ordered from either of these places. (Having said that, I also want to add that they both appear legit to me, and I'll probably order this stuff from one of them soon. Update: In fact, I did order each of these things from Katom several hours after writing this post.)
I've been meaning to order some of these pans and the gripper for at least a year, but I still haven't done it. Consequently, when I make deep dish pizzas, I've been using aluminum pans (which are much more commonly available than the pans I've linked to). If you are unable to find a source for steel deep dish pans, aluminum pans are not a bad substitute. Just make sure not to get aluminum cake pans, which are made of a lighter gauge aluminum.
If you buy this kind of deep dish pan, you will need to season it on the bottom and the outside, as well as the inside on the sides. If you buy a deep dish pan that's already dark, you will not need to season it. How to season pizza pans.