Honda Civic Rear Springs/shock absorber question

[jaxxs]

Hi

Looking for some advice

I need to replace the rear springs on my Honda Civic CTDI 2004

The garage I use were going to replace these yesterday but it seems
the bolt that runs through the bushes into the shock absorber is very rusty.

They are concerned that it's going to break/shear off when they remove it to replace the springs

So I'm trying to find a source of the bolts should this happen, and also wondered if replacement bushes were available ? as ideally I want to avolid paying for new shocks as well.

So any pointers as to where they can be obtained would be great

Cheers