If you want a pretty balanced mix of critical and block, the balanced longbow is for you. Or, just go to the bazaar and look for level 72 wands. At your level, theres not much block available at all. (42 is the max I think.) But at 75 theres something called the Wyrd-Oak Staff. I've used it as a boss wand on every character because it gives a whopping 72 block. I dont know if I would recommend it for you though, because the wand spell is ice, so you would use your blades getting rid of weaknesses.
If you dont care about weaknesses, I guess you could hit though the normal ones, but against fire (and death in pvp), I would carry a few cleanse charm treasure cards because of efreet and bad juju.