Tbh, I would suggest using Simplicity 4059, since he doesn't actually have a cape, he has these pretentious drapy things that come down from his sleeves. It'd actually be pretty easy to modify!
To add on to the types of fabric, you'll also need velvet for the red patches over the legs, and possibly muslin or taffeta for the lining of the jacket. I'd make the boot covers out of leather or pleather (unless you have boots that would work) and the pants out of suede, if you don't mind spending a bit more to be authentic. If you do, then I'd probably just make them out of a simple cotton.
I would /definitely/ second the mockup idea. With a costume this complicated that you would be modifying this much, regardless of how much experience you have, you really need to make a mockup with cheap fabric first.
Finally, the reason I found this thread was because I am currently working on a commission for this exact outfit for Halloween! If you would like, I would be happy to make one for you as well, or just to tell you any hints I find out along the way. Feel free to PM me!