Where can you find a suit of imperial silver armour in morrowind

If you're strong you can always kill one of Duke Vedam Dren's guards. He has four guards (they're not all in the same place), all of them wearing Imperial Silver Armor. Or you could take the longer but more moral way and just go to every Blacksmith in the game, looking for the armor. There may be another way that I'm not sure is true, but it might be. You could always try joining the Imperial Legion. As you go through the questline of the Imperial Legion you get Imperial armor, and at a high rank you might get Imperial Silver Armor, but I'm not sure of this so don't take my word on it. The other ways should work, though.