Bird's Eye brand offers smaller sized portions (serves 2-3) as well, though not as easy to find as the GG brand. Seems to be a bit better quality too, but you do pay for it (for budget watchers). My favorites are the 'baby' blends like the baby broccoli blend.
If you have a Super Target in your area, they carry quite a variety of veggie blends in their store brands -- Archer Market/Farms I think... Brain is a little tired. Varieties that I haven't seen in any other store, which is good as I like to switch things up on a regular basis to avoid food boredom.
Now if only FRESH veggies would come in smaller sizes. It's hard for a single person to eat a 'family pack' of salad fixings before it goes bad!