Oooh, bad timing... I saw a model of it less than a month ago. I'm not sure whether it was scratch bui8lt or not, but if it was from a molded hull, the builder did a fine job of finishing it with wood inside and out. The Queen was among a bunch of R/C scale boats on a temporary indoor pond at the York (PA) county fairgrounds -- live steam powered, too.

I saw it at a twice a year event -- next one's in August. Meanwhile, I'll see whether anything I have points to a club or something where I can ask about it.

What you might try (something the guys there pointed me to) would be to see what they have at the Mystic Seaport museum -- they collect plans for significant boats -- and I think the African Queen would qualify!