four days are numbered if you’re still using the excuse that your tennis talent is hampered because of the racquet in your hand. Prince lets you have your say-so with the Sovereign, its first custom-tailored tennis racquet. You choose head and grip size, balance point, weight, number of strings, amount of string tension, and flexibility of the racquet. Add cosmetic touches such as frame and grip color and where you want your signature to appear on the handle, then turn the four-week-long custom job over to one of Prince’s craftsmen. It’s $1,000 (including full-grain leather racquet cover and matching tote bag) at Brookhaven Racquet Club, 241-5961.