Edit 19.10.2017: So, I have still not managed to scan the orginal version, because its very hard to find local place that can make idividual A3 scannings. So i decided to trying to use Gimp for making the image bit more "readable". And here is the best result I could achieved. I hope it is OK attempt. ^^
Edit: 29.3.2018: Managed to finally color this. :3