I hadn't planned on doing anything immediately but after reading the recipe I had to make it. Since it was on a whim I found myself lacking a few things, but I made some substitutions and alterations.
First, I used salted butter instead of unsalted.
I used a 1/2 teaspoon of allspice instead of 1/4 teaspoon of allspice, to make up for the 1/4 teaspoon of cloves that I lacked.
I panicked slightly when I saw that I had no baking soda, but I read somewhere that for every teaspoon of baking soda you need, use two teaspoons of baking powder. So since the recipe calls for one teaspoon of soda, I added two teaspoons of powder to the 1/2 teaspoon already called for in the recipe.
The last substitution I made was olive oil instead of vegetable oil.
I baked my bread for an hour, then added four or five minutes, and the toothpick finally came out clean.
The best pumpkin bread I have ever tasted!
It turned out BEAUTIFULLY. Originally, I was going to make icing to drizzle overtop (using the same icing recipe I used on my pastries), but the bread was sweet enough on its own with a bit of confectioner's sugar. It was moist without being squishy or dense, the outside was sweet and slightly crunchy - I just can't say enough good things about this recipe. Even after all the changes I made, it still turned out amazing. I think I'll just make it the same way next time!