Many years ago (2005) I purchased Mirabilis 'Hot Glow' seeds from Thomson & Morgan. I usually dig up the tubers and store them over Winter. They do self seed, but if you save the tubers, you will get a much larger plant. Note that I am in Michigan zone 5. Hot Glow is my favorite:
Also, I have recently tried Sweet 4 O'clocks. they have really long necks:) I did these up, but they also self seed.
I have tried many different colors... broken colors, white, limelight, custard & Cream, Marrakesh, stars & stripes, and pink pin wheels. Sometimes the seed was not true to color or did not germinate well. Here is Hot Glow & Broken Colors. If you find a color that you like, the safest way to have it again the following year is to save the tuber (it's probably a root).
