Looks like they took a 700 and made options (shelves and such) standard and that’s what you have. I’m interested as to why they went from a SS deflector to a cast iron one.
Likely for long term durability. Stainless has a tendency to warp and deteriorate (carbide precipitation) in conditions such as this, directly over flame source. Cast iron is very stable and holds up well in such an environment, look at cast iron grates in old wood and coal fired heaters.
Looks a nice solid upgrade and offering to the grill/smoker line.