I ended up writing the letter I chose so many times. At first I tried to copy the letter forms from the original, but they were so eccentric that I kept messing up and being inconsistent. And I was trying to write it completely without any guidelines or lines of any kind, just like the original. I didn't do so bad with that, but not so great either. And then I wrote out a version I thought was good, then copied it twice before I realized I had forgotten a whole section. A common mistake of the copyist!
I ended up just writing it using my regular correspondence hand. By now I could almost write it out from memory with only a few promptings. But it was fun for me at least. I make no guarantees for my readers.
I'm sure, Scarlet, that any mistakes you made will look so good they'll be taken for how it was supposed to be.