I have an old Wahl Home Pro. It cuts at about a 0. You can go all the way down to a 00000 if you buy the right blade, but that is probably shorter than you want. I will be honest with you though and tell you that I think that you would look better completely shaved than with your current buzzcut.
If you don't like using a razo,r either stick with what you have or shave electrically with the Wahl 5 Star electric shaver. The 5 Star will shave just about as close as a blade.