Right behind the shock you can see the broken swaybar link hanging limp. The actuator globes are under each side of the truck, on the outside of the frame rail, right under the doors.
Rockauto.com always seems to have the best prices and variety. The actuators very rarely fail. The diving could be due to a failed globe or worn sway bar components. Try flushing the system and verify any leaks. Could just be something needs a new seal or tightened.
Sometime in the production range they switched to a variable rate rack for the LX470 (slows the steering sensitivity at higher speeds), but the dimensions are the same. You can find Borla mufflers for cheap sometimes on Amazon. I bought some not too long ago for $60ish. The LX does not use...
And I am guessing that these are a true progressive coil and not a dual rate like the similar extended travel icon and slinky rear coils? Also, do the shocks have an extended length like the OME L's and the Icons? Do you know the compressed and extended lengths?