If you are in or have friends in Japan, hunt down the Nanuk sketchbooks. The page is a soft cream color, with thread binding and absolutely no branding or logos anywhere. Unlike most sketchbooks (even those from Muji) these are nice and tall which is ideal for note taking and designing for web and mobile apps.
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The A6 Muji Dot Grid notebook is my go-to. Like all Muji products, it's unbranded and has all the attention to details you require. It's tape and thread bound, with a soft cream and a faint dot grid that helps your work stay tidy but won't cramp your style.
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The double-tip hexagonal Muji pen was a happy accident. The grip has a soft touch and the shape means it never rolls off the table. It's double sided so you can get a thick and thin tip which is great for wireframe sketches. The ink is a bit softer and won't bleed through paper like sharpies.
The ruler I have and love is 12-inches, clear with a metal edge. The metal edge is key for cutting paper and tracing lines (it also keeps ink off your paper). This one is a close comparison but has 90s style Marker-Felt font and dark lines. It's clear, has a metal edge and is on Amazon Prime. It's not sexy but it gets the job done.