The only dried mint I can find is spearmint. What kind of mint should I be using?

For Middle Eastern recipes, I dry -- in the microwave (!) -- the spearmint growing in a pot on the deck outside my kitchen. It would be cost effective for you to do the same, even if you have to buy a bunch of fresh mint.

Even if cost is not an issue, consider this: freshly dried mint is a thousand times better than the sad stuff sold in jars. Info on how to dry it using the microwave can be found here: https://www.maureenabood.com/technique-how-to-dry-mint/

This technique works well for hardy herbs like oregano, thyme and rosemary.

Hope this helps. ;o)

I would assume dried spearmint! If you already made the recipe let us know how it turned out for you.