In the pause menu? No, unless you're using RMXP, in which case, have fun scripting that one in (I'm not even touching that .. HORROR).

Anyway, in RM2k3 at least, you can set a 1x5 picture that will just be your bar, and set that to the width of a variable ([xxxx]Alignment, I guess).

Then use a keypress (or an item) to call a Common Event that will display the bar. You can even have another picture be the "background" for it, and have it scroll in.. whatever you want, really.

Not too difficult, I think I'll build a demo later.