Why buy it when you can make it? Instant oatmeal doesn't require any special ingredients, just whole oats, which I use in many of my baking projects already.
I found a base recipe from In Sock Monkey Slippers and adapted it to suit our family's tastes.
Homemade Instant Oatmeal
3 cups whole oats
1/4 cup plus 1 Tbsp. brown sugar
1 heaping Tbsp. cinnamon
1/2 tsp. sea salt
1/4 cup slivered almonds, toasted*
Combine all ingredients together in a bowl. Divide into 6 individual baggies or just measure out 3/4 cup when you prepare each bowl of oatmeal.
To make oatmeal, add 1 1/4 cups of water (or milk if you prefer). Microwave 2 minutes. Let cool to an edible temperature, and enjoy!
*To toast almonds, spread them on a baking sheet. Bake for 5 to 10 minutes at 350ºF, checking every few minutes to see if they are lightly golden.