I thought the problem was the broken drop link but noticed this when the car was up where did all that rust come from


I'm assuming this is a fixed part on the beam as i can only find top spring seats for sale.
Does anyone have a photo of what it should look like?
Haynes and parts catalogue don't show it clearly, it looks flat but i'm sure when i last saw it there were 3? welded strips supporting a raised seat
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On the brakes side, the months-old nearside handbrake cable spring has vanished. I think it was intimidated by the strength of the offside spring...

The part i'm after appears to be 90345813 but the catalogue's confused me, that's just the cutaway frisbee, the central part isn't greyed out.
If it's right, how is it held in place
