Large nut securing bracket to passenger side inner tie rod?

[myf16]

The guy replacing my inner tie rods has apparently messed up the threads on the large (aluminum?) nut that secures the passenger side inner tie rod to the steering rack, with a mounting bracket in between. This is a very large nut, with female threads matching the male threads of the inner tie rod. 

I cannot find this part on the Lexus parts diagrams. What is it and where can I get one? I suppose it's a standard but unusual metric size. 

The Lexus parts diagram doesn't even show separate inner tie rods, just the entire rack for $$$$. 

[RX400h]

My guess is that it has fine threads. If you have a micrometer or calipers you can measure the diameter which will be very close to a whole number metric thread size. Then look up a metric thread size table that has fine and course threads. You may also be able to use the correct tap and clean out the threads of the nut using tapping fluid.

[H53I]

https://www.amayama.com/en/catalogs/lexus/ls400/1-sedan-left-xf10-1989-3470/transmission-and-chassis-2/front-steering-gear-link-133
 

That has a lotta part numbers n some diagrams, might help

https://www.lexuspartsnow.com/parts/lexus-nut-castle~90171-12002.html?vin=&make=Lexus&model=LS400&year=1991&submodel=&extra1=&extra2=&filter= (d=USA)&location=power_train_chassis/front_steering_gear_link,,45046A

Thats the outer tie rod nut. Maybe theyre the same, if not it might help finding the inner nut.

Also I think I read that bolt is Left Hand Threaded.

[myf16]

Yes, it's 90179-40006 which is discontinued and out of stock. I found a junkyard part and will check for left hand threading. Thanks for the tip.