First stove Squirrel Morso B2 stove questions

I bought this old stove on marketplace, and now have to figure out what pieces I need to get the pipe through my school bus ceiling. It came with 2 5ft double wall pipe sections, I only need one section to make it through the ceiling but idk if there's a simple kit for what looks like 4.5 inch pipe.

HI Michael, Welcome to Permies! Are you making a tiny mobile house? How exciting!
So you're looking to find out how to get the flue through the roof? What is the ceiling made of? You'll need to keep a good clearance from flammable materials.

've been living in the school bus for a while but have been using a propane heater, which I guess has been producing a wet heat so I got the stove hoping it will help keep things dry. I used to rely on a dehumidifier but am living on solar power now and can't run that through winter.

The ceiling has some cedar and insulation but I imagine I'll cut that open and get some fireproof insulation. The actual ceiling is metal. I was hoping there'd be a kit like there is for 6inch stove pipe. Such as this kit my friend used for his 6inch pipe: Selkirk Metalbestos 6T-PCK Pitched Ceiling Support Kit Stainless, Stainless Steel https://a.co/d/3rRkLRJ