My L3301 came with one, but I think it's normal for it to be removed if not used because it gets in the way. It's removed if you have backhoe as well. Once removed (aka not in use), it's quite easy to misplace.
On delivery, mine was in the bucket. I moved it to shop and then some time later when I removed backhoe and installed hitch, I couldn't find it. It was sitting on a bench in clear sight, but was 'blending in' so it didn't catch my eye. It has a hole where you can mount a ball on, but I think mostly designed for tractor pin mounts