I dunno what items I should buy because this is the first time I made a Crit Lock
Pvm Weapon: Various Jur[4], 2x Mobster, 2x Soldier Skeleton
Pvp Weapon: Various Jur[4], 4x Assaulter Card
Upper: Feather Beret (Preference really, some people like Berets, others like Evil Wing or Bunny Band)
Middle: Sunglasses[1], Ungoliant card (immune to bleeding, counter various jur)
Lower: Gangster mask (or some wings if your server has them)
Armor: Thief Clothes[1]//Chain mail[1], (whatever you want really.. probably an Evil Druid Card)
Garment: Manteau[1], Raydric Card//Whisper Card
Shoes: Boots[1], Matyr Card
Acessories: 2x Rosary[1]//Brooch[1]//Ring[1](preference really), 2x Kobold Card
These equips only bring you to 37//38 crit So you need to boost luck 30~40 points. This is going off 99/70 of course... and just my personal preferences. Hope it helps.. You could try for full Morrigaine's set, never had it... so dunno how well it works.
morrigan set is really nice for crit builds. i havent tried for sin but i tested it on my falconer in my alpha.