I have lately found some very similar products on Amazon, that do not require the vacuum cleaner and seem to be more cost effective:
Nosefrida The Snotsucker Nasal Aspirator
I haven't tried any of them personally but they seem to have the same concept as the Nose-Vac that has been our wintertime life-saver for over 4 years now. By the way, we often skip the vacuum part and use our own lungs to help kids breathe, especially at nighttime.
As for the cough,.. I am still quite at loss how to fight it. Another friend of mine, a mother of four, has recommended Echinacea/Astragalus herbal supplement from Herbs for Kids. She says it has been her go-to remedy for a couple of years now. I give it to my kids at the onset of the coughing along with Kid's Cough supplement from Sun Harvest. I am not as consistent with it as I should be, so my results are not as great as I'd like them to be. My MIL gives kids warm milk at bedtime and Pertussin (an herbal cough syrup we get from Ukraine). Combined together, these remedies seem to soothe the cough but nothing has proven to completely get rid of it. Perhaps, you might have tried and true remedies that work like a charm for your little ones?..