The only tool a witch absolutely needs to work effectively is herself. Tools do add the energy invested into them by the witch and her Divine connection into workings, but don't think that in the event of widescale persecution (may it never be so!), and in the event that a witch was ever denied her tools (may it never be so!), that she (or he) would be incapacitated. It isn't true. There have been times when all I've had to use was my essence, soul, mind and some small physical action.
I don't think it's a good idea to cultivate the idea that a witch needs her tools to be effective. A witch needs to destroy that idea. I love my tools, but in the end, if they were stolen or taken from me, the energy I've invested in them would immediately return to me. I also think a witch does need to cultivate this latter idea - that the power invested in her tools belongs to her and can never be stolen or taken away.
If a witch lacks some prescribed ingredient, invest another ingredient with the kavanah to carry out the purpose of the ritual. The soul and essence of a witch is empowered to do this.
In Judaism, the power to do this is called Da'at Torah.
As a witch, create the reality which surrounds your tools.