Anyone know if the plastic connector that holds the wiper to the arm can be replaced? And if so, where can I get one?

 

I don't think you can buy it on it's own. Though I have a few suggestions.
Do you have an old set of wipers you have not thrown out? There will be one on them.
Buy the cheapest wiper you can find and just use the clip. Look in the trash cans outside your local parts store, I'll bet there are about 20 wipers in there with the clip on, or even a packet with one in that was not needed on that model of car.
Hope one of these saves you buying a whole new wiper.