As I've mentioned in various places, the prices for apparel and racquets are basically the same online as in physical shops. That means that unless you have a gym nearby (which usually means a local shop, too, though usually with more selection in racquets than clothing), your best bet is to check prices on the two main online sellers, and then visit their physical shops if you're still interested. See details here.
The Badminton Mart store is here. If you change to the map view, you should be able to find it exactly. I can't do it with Google Maps because it doesn't have an updated street view photo but it's here.