If you want to pick them up at York I would suggest contacting the dealers now and ask them to bring what you need. I have had no luck finding them there but a few dealers like Norm's O scale said they had them but didn't think its worth bringing them to York.
I get mine from English's hobby aka Bowser, in Montoursville, PA. They stock the complete line of Kadee. They don't do York though.
Pete