For those looking to customize their watches (especially the Seiko SKX or SRPD lines), these shops specialize in aftermarket "mod" parts like sapphire crystals and ceramic bezels.
: A highly respected US supplier often used by professionals for high-end or vintage parts.
: A long-standing Canadian supplier that offers a wide array of movements and comprehensive repair kits.
: A German-based shop offering a deep selection of spare parts for brands like Omega, Rolex, and TAG Heuer.