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It depends on what you want really. If you are looking for full leather suits and racing boots then you will have to shell out some cash anywhere you go. If you just want a jacket and some gloves then you should find a good deal out there on the net you just have to search around becuase the best deals change from day to day from site to site.
Make sure you go to a local store and try on the stuff you plan on getting just so you can make sure you are getting the right size. Many riding apparel companies (Alpinestars included) are in euro sizes. Most of all riding gear comes in suit sizes for men so unless you are familiar with these units of measure then guessing your correct size can be a pain in the ass; unless you try on the exact thing you are going to buy. You will be glad you did.