This mod adds items bearing the alphabet, numbers 0-9, and !?
These are just items, not blocks, but they can be placed in Item Frames to create labels.
I personally use them for frequencies for the Create mod's Redstone Link.
Main "Blank Plate" item is crafted with three Smooth Stone Slabs in a horizontal line.
If you have another mod that uses this recipe, I would recommend the mod Polymorph to resolve conflicts.
From there you can switch Plates freely between symbols in the Stonecutter.
This is something I threw together in MCreator because I wanted it for myself. Do not expect updates.
