Spirit runeword.
Note: Weapons on normal cant drop with 4sockets. They start dropping with 4 sockets on nightmare.
The recommend place to farm those swords on normal is the Cow Level. White swords can be socketed using the Larzuk quest it will give the max sockets.
The formula to roll the sockets on swords in the Horadric Cube is:
Amn rune + Ral rune + Perfect Amethyst + Sword
When u click transmute a 1d6 dice is rolled, if the result is 4,5,6 you will get the 4 sockets. 1,2,3 result will ruin the weapon. So you got 50% odds to get what you want.
Spirit shield
Monarch shield: Str req 156 ilvl 72 The most common places to farm it is hell cow lvl or area level 85
The other shields who can get 4s got are Aegis 219 str req!!! and Ward 185str req!!!
Only paladins shields can be better than monarchs for spirit shield.