This is an interesting and challenging problem, for sure.
It's one thing when one partner is more private in general and the other is more open. My girlfriend often blabs details about our sex life to anyone who is listening, whereas I am more private. That's much easier to deal with.
The issue for you guys is that if you can't be more open, it effects your dating potential.
If she's more open, it might affect her work and so forth?
Well, there's the opinion that she shouldn't care what people think or how this effects her. I'm extremely open about my life choices and truly do not care if people don't approve. If I don't get a job, or I lose friends or family, because of this, I see it as a blessing in disguise, because I couldn't be myself in that environment anyway.
But of course, work is money and money is food on the table. So I understand that it's important. In your line of work, is it really a problem? I'm in a creative field and whilst, in England, nobody I know has heard of poly, after a short question and answer session, it's not really an issue with the creative people I am around.
One option, as others have said, is using certain dating sites. I see your problem with OKCupid, because it's not just for poly people. I wish I knew of other poly dating sites, because I could use some myself to be honest!
Do you use FetLife? I know it's not a dating site, per se, but if you are submissive, this is your best bet for finding events and people who are kinky? And, for some reason, poly and kink seem to go hand in hand often. Or at least, those who are kinky are probably not going to blab your poly secret by seeing you on FetLife - because they'll be blabbing their own secret about being kinky!
Another avenue... a half truth? You could display your polyness on OKC and so forth.... but she can pretend that it's only you doing this. She may still get judged, but most likely, their daggers will only be pointed at you
And you seem able to deal with daggers.
So maybe it would be an acceptable compromise that you can be open online and keep looking that way for now. Perhaps treating local people as if they are no-go zones, the same way some poly people have a rule about not dating exes, or best friends, or colleagues?
Perhaps eventually it will come to a crossroads - if you've been unable to find someone and you're really needing to find someone, if poly is very important to you and you need that dynamic... well... Something will have to give?
Other than that, are you at home much? Have you considered online play? I used RLC/Utherverse, which is essentially a kinkier version of Second Life. Like you, I am at a slight disadvantage. My girlfriend is seeking guys who like women (plenty of those), who are submissive (plenty of those), in her area of the US (practically the kink and poly capital of the world). I'm seeking women who like women (cuts my numbers down), who are also poly (cuts my numbers down when I'm in the UK), who are kinky (more number slashing), who I actually find *attractive* (that leaves about three women a year). ~grins~ RLC greatly helps me to take the edge off kinky interaction, social and romantic interaction, when i'm struggling to find someone in real life. I have also actually met a good handful of women I would consider meeting in person, who I never would have met in real life, or on a dating site.
It might not work for you if you're touring a lot... but I guess my overall advice is to perhaps think outside the box, think about how strong your poly need is, weigh the risks and go from there?