Crafting of weapons/armor is still semi-functional in both modules. I was able to get a dwarven waraxe in the OC by looting two shield golems in the epilogue of chapter 2. However, if you need a break-down of what you need to implement at least basic NWN crafting here are the items that you should give to merchants.
Weapons/armor:
Feathers
Bolt of Cloth
Leather Hide (in OC and SoU there should be plenty of this from monsters alone)
Plank of oak wood
Plank of elm wood
Ironwood planks (used for higher AC shields)
Bar of iron
Bar of steel
Bar of adamantine (optional, used for higher AC armor and helmet)
Bar of mithral (optional, used for lower spell failure armor and a shield that gives freedom)
Traps (already implemented in SoU)
Acid flask
Alchemist fire (I think this can be found in OC)
Caltrops
Choking powder
Coldstone
Holy water
Quartz crystal (in OC)
Skeleton's knuckle (in OC)
Tanglefoot bag
Thunderstone
Spells
Blank scroll
Magical potion bottle (not magic potion)
Bone wand (can be crafted from large bones)
Poisons
Centipede venom
Giant bee venom
Spider venom
Light gems (any color)