I'm a longtime Isaly's collector, I was hoping MTH was coming out with a new car...
Based on the link you provided, this does indeed seem to be a new Railking Isaly’s Refrigerator car. Too bad there’s no photo. BTW, there are two different cars listed on the website as in addition to one in the link, #30-78207 with road number 586, there is also a #30-78208 with road number 589.
There appear to be several companies selling Isaly's branded products. One of them is a company called Conroy Foods in Pittsburgh and their name is listed after the Isaly’s name on that linked page.
More cars for yinz Pittsburghers!
Bill (a native yinzer in Florida)