Adler 20-20 restoration

[Asentaja]

I'm restoring old Adler 20-20 machine. There is however few critical parts missing from it. I know it would be very difficult to source these missing parts for such old machine, all leads would be appreciated.
I have not found any parts diagrams for this exact model, so I don't even know what I'm missing exactly. I know that I'm missing presser foot, leftmost slide plate and needle clamp. I do have original bobbins, but I'm missing shuttle hook and holding parts for that. 
Based on dimensions of my original bobbins (43.9x32.4mm), I have figured out that hook that I can find with part number #58669 could work, apparently it's used on Singer 7 series along with some other models. If that hook fits, I still need parts that keep it in place. 
Can anyone confirm what I'm actually missing? Is it just one part with fours screws keeping hook in place, like in Adler 120 (diagram here), or more similar with Adler 20-2 where there is two parts and spring (Singer 15K style)? Based on four threaded holes I have there, I'm guessing first mentioned Adler 120 style part is probably what I'm looking for this machine. Other than that, my machine looks very complete, however before diving more into this project I need to find these parts first. 

Can anyone confirm anything from my thoughts here? Could that (#58669) hook work in this machine? I have not found dimensions for that part, or photos of original hook for this machine. Is it possible that adler 120 part for holding it in place is identical? Any other machines that could share parts with this, or have parts that are more easily available and adaptable for this after some modifications? In best scenario someone here has obsolete old stock spare parts available for this, or has similar behemoth in his garage as a doorstop and wants to sell me some parts from it. Or at least someone here has this same machine and is willing to take some pictures and possibly measures.

 

[Constabulary]

I may have a hard copy of the 20-20 parts list, not sure though. I´ll check that in the days to come... stay tuned... 😉