This is a serious equestrian shop that is worth checking out, even if you've never been on a horse. Besides being a full-service tack shop with sportswear, horsewear, and equipment; Haven recently expanded (as its neighbors dwindle in the corner shopping center at the meeting place of County Rd. 39 and Montauk Hwy.) and has set up a room full of antiques (only some of which are horse related)....