Boure's PRO shorts and bibs use a traditional synthetic leather chamois.

If you're shaped differently than the average cyclist they'll do custom (different rise, inseam, bib suspender length) for 20% more.

I like mine a lot - they don't get uncomfortable after a few hours like contemporary designs with thick soft padding.

I also like Voler's Comp HP pad. While 12mm at its thickest, It's thinner in places, and has 120 kg/m^3 foam beneath your sit bones so you don't sunk. They're the one modern short I'll wear on rides over a few hours.