I still couldn't narrow it down.
Here is another suggestion, try posting the same question (as much detail you have on him in one post as you can) on the Swedish forum http://aforum.genealogi.se/discus/
(free of charge but I think you need to register in order to post a question). There is a thread there where you can ask questions in English and the people there are very helpful. They may be able to help you out.
I hope you find him!
All the best