The Cub-189 Two Way Moldboard Plow Manual is on the server. I have one and it is complete, now. Don't work too well without the latch bars, they are pretty much a must as is the Latch Bar Assembly. Don't forget the Brace.
Gord and I both have a 189. Unfortunately we only had half of the latch bars (both left handed). I got a pair of rights from Tom at TM for a good price. He probably has the complete assembly -- oops -- check this out - Latch Bar Assembly
Looks like the guy wants around $250.00 for the 189, it may be worth it to pick it up if you are close by. Then order up the assembly from Tom.
Btw, a complete Cub-189 is worth between $350.00 and $500.00 depending of course on condition up here.... so at $250.00 it would be a pretty fair deal.