I know of a clock themed stamp set designed by Kelly Panicci for Sandylion that has this phrase, but I suspect it was already discontinued by the time I bought it a few years ago.
If you can't find one, download a neat font onto your computer and print it off in whatever color and whatever size you want directly onto a piece of cardstock. You can then cut it out, mat it, and attach it to your layout. I do that a lot, but then I'm addicted to fonts!
