Ebay is good for NLA and NOS parts.....use a site like Crowley marine or marineengine.com to get part numbers....they have parts diagrams and sell some parts too. But the discontinued parts can usually be found on ebay.
https://forums.iboats.com/threads/%E2%80%9892-force-40-shift-shaft-seal.766074/ This thread from a couple days ago talks about the shift shaft seal removal.....
This is the pin that secures the shift rod, held on with a cotter pin. Should push out....no need to spin anything. Looks kinda corroded, maybe spray some penetrant on it and work it out......just be careful and not bend the shift rods......
Have heard some folks don't even bother using the seal and retainer.....will run fine without them. If you have the parts I would use them....they are supposed to be on there. No telling where the copper ring is, may not have been installed by the PO. Might be why the seal was laying there...
Don't have any vids or pics.....basically slide the retainer down on the driveshaft with the cupped side up, then slide the seal down onto the retainer where it seats into it. Then install the lower as usual.....tricky part is not hitting the sides and knocking the seal off before it engages...
Mine looked just like that.....I used Permatex Optimum Gray with new gaskets....never had a problem. I agree, it looks bad...as long as there are no holes in the plate and it is sealed up good it should be ok. Maybe jerry or Nordin will chime in with their take on it.
Don't have to remove powerhead from lower section. If this motor has been used in salt water the head bolts may be hard to get out, fresh water should be ok.
Mine was like that on my old powerhead.....asked around and was told it was fine, not to worry about it. Even if you got it flat again it would distort over time they said.
There are several bolts that hold the cover onto the head.....but all the head bolts go through the cover, so the head bolts will have to come out to get the cover off.
Didn't have access to my manual.....got that info from Mastertech marine....they have more torque specs listed also. Go to Technical Specifications tab, then Chrysler/Force tech specs.....