I also have "hard disk direct" ( no spaces ) bookmarked, another "see oh em" site. They have motherboards, etc, while the first site there seems to only have disk drives, now.
The default answer these days seems to be ebay and facebook, sadly. Found that out last week when asking about retro computer hardware.
If you have a big order, I’m sure most sellers speak English and might be willing to ship outside of NL (at your risk).
1. Local people who get them from auctions.
3. Web sites run by companies selling the PCs.