Burnbaby is a pair of very nice realistic fx styles for Photoshop. No needs special font, but for the perfect realistic view, i suggest to use rounded or even more custom fonts. You will get better solution with a bold, cracked type. Using a real texture will give you the perfect upshot. You can freely resize the file i have already tested the actual .psd file in 600×600 1200×1200 and 2500×2500 pixel sizes.
Adobe .PSD file with organized and named layers
Adobe .ASL file with well understandable names
Free font used: STAMP ACT © Harold Lohner
Download: http://www.dafont.com/stamp-act.font