It's possible that your dogs will get past their upper respiratory infection, given sufficient time if their symptoms are secondary to a virus as opposed to a bacteria. It might take 7-10 days for the infection to run it's course but in the meantime I do have a few suggestions which may help them to feel better.
1 Nasal decongestant drops can be helpful although many dogs don’t like them very much as you can imagine. The medicated ones (a-c below) should only be used for three days in a row, with one drop in each nostril; otherwise what’s known as a rebound effect may occur. This is one reason why I prefer "d":
a. Pediatric otrivin=0.05% xylometazoline
b. “Little Noses" Decongestant Nose Drops with phenylephrine hydrochloride
c. Afrin (oxymetazoline)
d. "Little Noses" Saline Spray/Drops non medicated which can be used more than three days in a row.
2. Cough suppressants can be given although I'm often hesitant to use them if kennel cough is the problem. I want those secretions removed from the upper airways and I rarely want to inhibit this reflex.
But acceptable ones to use include Dextromethorphan: http://www.petplace.com/article/drug-library/library/over-the-counter/dextromethorphan-robitussin-dm
The dose would be 0.25 to 1 mgs per pound 2-3 times a day. You just want to double check labels and ensure that the formulations only contain this ingredient although inclusion of Guaifensin is fine.
3. Believe it or not, probiotics have been shown to help strengthen the immune system which may help them to fight off their infection a little sooner. Forti Flora is a good one which may be available at local pet or grain stores. It can be purchased online but would have to be shipped over night delivery for it to arrive in time to help.
As long as they're eating, reasonably active and not in respiratory distress, then I might continue to monitor the situation before having them seen.
I hope this helps. Deb