I haven't been chasing very long and perhaps my sights are not set too high, but the first one on my list would have to be a Western Electric 554 in Oxford Gray. That would complete my collection of those colored sets, except maybe for clear if they made them in clear.
If and when I do pick up that phone then I will refocus my sights. Like I think you said you did Doug, when I get out of the car at the next flea market, antique shop, whatever, I say, my blue 302 is here today.