It may be worth tossing a can of balls in the luggage since it is cheaper to buy them at home. There is a tennis pro at WDW - Michael Dublin. Currently he is at the Contemporary and the pro shop is open and has racquets and balls as well. He probably has some demo racquets. He also gives great lessons and will come to Boardwalk if you ask (I have). The two courts at Boardwalk are hard courts. The courts at Old Key West, Contemporary and Saratoga are Har-Tru (clay). I usually play everytime I come down and I bring my racquet - so far I've put it in the overhead bin on the plane with no trouble.