+1 on CaliforniaCajun's advice...

BTW...There are any number of U. S. online vendors who sell DE razor blades, including Feather. Some of them advertise here at SRP.

Here are the links to two online retailers that I have ordered DE blades from in the past. One offers blade sampler packs.

Razor Blades & Cartridges | Men's Grooming, Skincare, Shaving, & Facial Products

Double Edge Razor Blades