Slip a plastic bag over the inside pages for protection. Spread glue evenly over the cover, attach a sheet of lightweight cardstock butted to the black binding (this is a kraft pack of 50 from JoAnn's), smooth out with a barrel ink pen or roller. Open cover and trim cardstock with utility knife or scissors, remove any excess glue on the inside, do the same to the back cover, stamp! You could also print something on the cardstock first. If you do, make sure to protect it with Krylon's Matte Finish 1311 spray or ModPodge before gluing. I'm sure I could do a sampler, but I have other journals for that and I like the simplicity of these.
Wouldn't the tiny ones make nice favors or place cards? A verse or quote printed in a nice font? Lots of possibilities and the best part - they are really cheap so mistakes aren't costly. The only problem I had was using too much glue on the edges and it seeped to the inside of the cover, and while drying they warp. I held them closed on the very edge with rubber bands for an hour or you could use a weight. Centering a nail file or cardboard strip beneath the covers before this was helpful, makes the cover bend in slightly. For my mache journals another paper glued to the inside of the covers prevented the warp. Now. Did you really need all these details?