Something that small just get a brush and roller and go at it. With a paint sprayer I’d recommend back rolling it anyways, so no need to spray. It really won’t save you that much time.

Since you’ll only need a couple gallons, I’d recommend Sherwin Williams Emerald Rain Refresh. It will last the longest and it’s amazing technology. Spend the extra money on a high-quality paint.

Let me know if you have any more questions!