if you're in the market for something slightly bigger, I've found this font to be useful on lowish-res (640x480) displays: https://github.com/josuah/miniwi
Weird that the lowercase letters with ascenders are taller than normal uppercase, I didn't notice that. But yeah, the core numbers+uppercase box is 3x5 (with only "Q" violating that). And it's all on a 4x8 grid.