Boots should be available at rubber parts shops.
Problem with Kabli springs is that they are also used and you don't know how soft they have become.
My Liana's rear springs are sagging a little. I am planning to get slightly thicker springs of some other car in same height. Spacers might not solve the sagging issue completely.
I had the same issue with my 85 Charade at rear and silver spacers didn't help much so I got 82 Corolla rear springs installed which worked really well. Could have been the added weight of the CNG cylinder.
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