Back in the day Robbie and Jill were a Mystere dealer. Maybe the only one in the country? He said he got involved with the Mystere before the T's because it's similar to the T. They are not a Mystere dealer now. Last time I was at their house they did have some parts for Mystere's. Not much but it's worth asking before calling Mystere.
I haven't read that part of the book in a while.(about the 19) The sail plan of the two boats are way different. I can tell you where I have my rake. Take one of you trap wires, disconnect the shockcord and tie a longer line to it. Touch that to pin at the bridle tang at the bow. Then holding that spot on the line go to the back of the boat and that spot on the line should touch the top of rear beam just behind the track.
I crewed for Bob Curry on my boat once. He set it up and I haven't varied much from his set-up. It must be close, we corrected out over Robbie on the M20 he had. So the boat can be competive. If you like I'll get you some measurments. PM me.