Old-school 2D RPG-style menus

I'm in the early stages of trying to make a retro-styled 2D RPG, like the ones from the SNES era. I'd like to either obtain or create a simple GUI system for handling menus that looks and feels like the ones in the games from that era.

By which I mean: you have a box pop up with a number of options, and then a little icon that you can move around with the controller to select from those options. Some options may open other menus (for instance if you select inventory, that will open up a list of items, and then selecting an item, will allow you to use it or drop it).

See examples here, here, and here.

I've been searching the asset store with queries like: "2d menu", "menu", "rpg menu", "rpg assets", etc. and have been very surprised not to have found anything for this. I've found several pre-made assets that are menu-oriented, but they all seem to require using the mouse, which is antithetical to the retro feel I'm going for.

If there's nothing out there like this, I'm prepared to make my own I suppose, I'm just surprised that I can't find one pre-made. Even in the complete RPG asset bundles I look at, the menus don't look and feel like the old-school ones.

I was wondering if anyone out there either...

A) knows of an asset package that would fit my requirements, or...

B) could give me some sage advice on the best way to go about making a menu like the one I'm describing? For instance, I've already figured out that it would be best to create an empty object which contains GUI elements and creates them with the OnGUI() function, but I don't know where to begin when it comes to creating an icon that the player would control to select between them (because the world position for game objects doesn't seem to always line up with 2D GUI positioning).

Any advice would be greatly appreciated. I'm ready to dive into this, but I thought I may just ask around before going off in the wrong direction.

Thank you!