Yeah - sorry about that. The text/links got crossed in the midst of my failed first order and change to both size and model.
What I ultimately ended up on wheel-wise is the Type 73:
I ended up 19", not 18" in the end. The wheels are still the Sottozeros.
Has been working really well, though I put them on with the first cold weather and then we promptly had unseasonably warm weather constantly after until recently. Now we're getting ice and snow, but I've had no cause to actually drive on it other than a minor test around the block a week ago. We are at least consistently having weather below 40 degrees, which was the bigger reason I went with the winter tires than the amount of snow and ice we get (though we do get some every year).
Not sure I can speak to the load rating with any real knowledge. I just know everything in the kit was declared compatible with my M3P and I've certainly seen nothing to suggest otherwise.