To get started in the Amazon Associates program, you’ll need to have a website that meets Amazon’s site requirements. Next, submit an application. If it’s accepted, Amazon requires you to place its affiliate disclosure on your site. The Federal Trade Commission also requires affiliate marketers to clearly disclose their relationship with retailers in posts containing affiliate links. That means affiliates should make all disclaimers easy for readers to find.
If there’s no products on Amazon for “High end” then you have no Amazon products to promote and no way on earning any commission. Why not try keywords like Best (x) or Luxury (y) where there will be more search volume. Let’s say you want to promote hammocks, you can then target search KWs such as Best Hammock for Under $100, Most Comfortable Hammock, Luxury Hammocks etc. Let me know how you get on.