If your ever in need of a Zener Diode that isn’t in your inventory, sometimes you can remedy the problem by soldering Two or more of them in a series until they add up to the needed voltage. When a friend told me about this technique I was sceptical that this could work, but after trying it myself I was happy to see that it does. If you try this just makes sure you have the polarity correct and the wattage of the Diodes. The wattage will not add up as the zener voltage does. The wattage will only be as high as the lowest wattage diode you use.