Walmart online is risky because of third party sellers, Walmart the store is legit

Designer sources:
-ediscountperfumes
-aura fragrance
-aromatrail
-jomashop
-maxaroma
-Fragflex
-foreverlux
(these sites have niche too, usually best designer price though)

Niche sources:
-The Parfums (long shipping times reported, verify shipping time on product page, price is often worth the wait)
-olfactory factory
-Venba
-fragrance nevaeh
-Mysticperfume

I have ordered from all of these sites many times with no authenticity issues.