I have been asked by a number of people about the gypsy queen engines I bought a number of years ago. I got a hold of a fellow through Langdon Badger(he is on this site) who had a stash of gypsy queen engines and parts. He was located in Australia. I don't have the fellow's name anymore due to a hard drive crash. The fellow suposed to have sold the remaining inventory to someone or some company. I bought 4, two were "pickled", 1 is being rebuilt, and 1 was trashed, the block being cracked. The pickled engines I bought from the fellow came from the Shri Lankian air force. Unfortunately all 3 have been spoken for.
You guys can google gypsy queen engine and come up with some info as to where one might find some engines. Argentina bought some and or built under license a dehaviland that used the gypsy queen. Here is a link of a company in england that might have some stuff.
http://www.devonair.net/services/mar.htm
I guess you have to beat up the bushes to find some.
Hope this helps.