Rebuilding, need tips when buying bearings on parts shop 190E

[ivanlee190e]

Ok this is concerning the engine block, without the engine head.


I need to rebuild this '88 190E 2.3 8v engine because I can see with the head removed that the last piston (near firewall) is bad because I can see the ring, apparently, the car overheated and a small section of the piston edge melted. So, I will be "transplanting" one piston from another '88 engine that I have (which is also bad but I assume I can get an OK piston)

I was searching through parts shop/fast lane and the piston rings sold there have a picture that only shows 3. Can someone explain that to me ??? How is this going ??? Total amount for rings for all 4 pistons ???

It looks like I will be needing piston rod bearings too.

What else do you think I will need to buy now that I am thinking of ordering from mercedesshop?????