Go to zappos.com, in the Search Box- type “Koolaburrra by Ugg slippers”. scroll down past the flip-flop styles, the ones I got are “Leaky Perf “. One of the answered questions say this style is for women, so I entered “Ugg slippers for men”, and there are similar styles- check out “Ansley”.
My daughter and her family order almost exclusively from Zappos and are very pleased with their products, customer service, and return policy. I looked for myself after observing that the features of her Ugg slippers were just what I needed (stiffer back, non-skid sole, inside cushioning). I’ve googled how to wash the interior, it’s easy to keep them clean.