I found some plans for the Seeadler at "Taubman Ship Plans" you may find what you need there.Hello Bob,
You are right. The available kits are not accurate and the only relatively good drawing I have seen it the one I attached. I found it on eBay, but it had been sold and I was unable to contact the seller.
While I am almost sure there are no plans of the Seeadler, there may be some of the Pass of Balmaha somewhere. There are a few scratchbuilt model out there, so there is a chance some good plans (with hull lines) exist.