You could try inductive heating of the nut till cherry red as that frees the rust. I would not use a gas torch near the fuel tank…. I have had to cut them of before now. I think the “bolt” is available but not sure.
If we're talking about the panhard rod Omicron supplied me bushs and bolts
But I can't help if it's the anti roll bar, as series 1 Berlina doesn't have one!
Brian
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