Thanks for the kind thoughts..
The vet finally got back to me, almost a full day later (good thing it wasn't an emergency!) .. Anyway, last night he wasn't coughing as much as he was before, and so the vet said to watch him tonight, but if it continues into tomorrow, I should bring him in and get an x-ray (add another $200 to the $600 I've already paid .. man, I should have been a vet!) .. to see if it might be bronchitis or asthma..
So I'm keeping an eye on him, and hopefully he'll have improved even more tonight than he did last night (he purred a lot and only coughed twice!)..
Crossing my fingers! Julia