Hi D
There is a site for Luft 46 Aircraft on the web .It has most of the resaerch aircraft and has the kit info if one exsists. The site is luft 46.com . You will find it on Google . Best of luck with the modelling
The Arado E555 is a nice kit, if you find one go for it. I have one in my stash and will get to it one day. There are a couple of other good kits that Revell do as well, 2 versions of the Me P1099. fighter and heavy fighter I think? good luck with your search...