https://itch.io/game-assets/tag-user-interface
If I search for it like this, there are some results which would seem to match your description. If none of them are what you are looking for, we would need to get a bit more specific it seems. For example, can you remember if it was a free or paid article? Was it intended for a specific engine? You can try to use some more filters and/or tags based on that. That being said, you have to consider that not everyone uses the same tags (or categories). So if for example you used the 'Pixel Art' tag to search for it, the author may not have added that as a tag for the product page.
Another way would to think about a more detailed description of how that UI looked, so it may be easier to find it by going through the results.
