Might I suggest "Derby" blades. They are relatively inexpensive. I have had very good luck with them myself. You can pick them up on the bay for about $10 for a hundred with shipping. As far as taking a de apart it can be done to a point. Depends on if the handles are rolled on or screwed on. Also if the screw in the bottom isn't buggerd or gooed up. That screw is left hand thread!!! Remember that!! And you will have to make a tool to get it out. A simple small screwdriver with a V notch in the bottom will work. Enjoy!!
Ray