Yes… and no. They need to be internal 4TB sata hard drives of reliable brands (we went with the Caviar Blue ones). To keep the costs down they would also need to be sent from Europe and not needing returned. All things considered, buying them directly from Amazon with the donated money ends up being the cheaper option.
Okay, just checking. I figured there might be some users in Europe who might have some to donate and/or have a connection to getting cheap HDDs.