Missing part

First first time poster here so go easy. Alright here's the issue. I bought my runner with a busted balljoint on the driver side. Got her cheap and it's the best $750 I have ever spent. The problem I am having is on the lower control arm where the ball joint bolts through I am missing an odd shaped washer.

Now I can not find any reference to this washer anywhere and even the dealer has no clue what I am talking about. I can take a pic of the spot where it goes. It's as domed washer and with out it my ball joint just comes loose. I have has to just put a large washer in its place for now but the ball joint keeps coming loose since it is the wrong part. Now I have a junk yard I can go to that has a cpl runners in it. I just need the name of this washer. It doesn't appear to be on the passage side.

 

It goes under the nut for the lower ball joint. I can't find any reference to this part anywhere. With out it the balljoint nut ends up going into a bowl.

 

Here is my problem. What is missing? Cause the nut fits all the way in. So I put a grade 10 washer on it so I could at least drive but it's eaten up the new ball joint and the nut.

 

I would just buy a new ball joint from Toyota

 

I replaced the lower control arm since it turned out that the previous owner drove it for a long time with a loose balljoint and the nut hammered into it.