In lieu of making a starter, you could simply buy (and pitch) more pouches. But starters have other benefits for liquid yeast and making them is a good habit to get in to.
I have gotten away with direct-pitching a single fresh Wyeast pouch in the past...but there have been more times that I did not get away with it. YMMV, but simply put, it's a bad idea to direct-pitch a single Wyeast (or White Labs) pouch. Wyeast's marketing says you can...I don't know how they can claim this with a straight face.
As a side note, IME it's different with Imperial yeast. Yeah it's got more cells, but even old Imperial pouches take off like a rocket. They must feed their yeast steroids. I have no qualms direct-pitching even an old Imperial pouch (although I still make starters for them).
If you are going to Morebeer anyway, it's not a bad idea to pick up some dry yeast packets. They can sit around forever and are good to have on hand for "emergency" situations like this.
Cheers, I hope this wheat beer turns out great!