The front struts (yes I said struts) for some cars can be rebuilt. The tops unscrew and then you pour out the old oil and pour in new motorcycle fork oil (or engine oil???). I know that the original Datsun struts for a 510 are that way, as are most of the late 60s early 70s Datsun struts.
So for the front of your metro, you should drop the struts out and check that out, it may just require an oil change.
Another alternative, which works for both strut cartridges and Shocks, is to go to the Monroe Shock web page and download their application catalog.
1. Find the part number for the metro Front and Rear strut/shock.
2. Go find that specific strut/shock and write down the specs: diameter of strut cartridge, length of strut cart, length of travel, anything else interesting. For the rear shocks, know the max and min length, and type of attachment upper and lower.
3. Then go to the cross reference charts and search for similar size/length/attachment, and also shorter length/same attache mt/same diameter parts, write down all those numbers.
4. then go back and find out what cars those fit.
5. Then pick from those cars, for stiffer shocks, pick a heavier car, like a Chevy Camero rear shock that is a little shorter, but has the same attachment types U&L. For a softer shock, pick a lighter car (tough to do for a Metro). For a lowered car, pick shorter overall and shock length. for a Rally set up, pick a longer travel shock.
6. Hit JY, find the right parts, unbolt, take home, be happy.
Dudes Ex Machina:
https://www.facebook.com/dudesexmachina?Everyone who has ever built anywhere a 'new heaven' first found the power thereto in his own hell- Frederick Nietzsche