As I reported some months back, Kaiju Blue, the short-lived but venerable shop which hosted many fantastic shows, closed its doors. However, its webshop has stayed open. And they've got some nice sofubi for sale, from Real Head, Blobpus. Sunguts, Uamou, and more.
The good news for collectors outside of Japan is they'll ship internationally. Plus, you can write to them in English.
Click here to head straight to Kaiju Blue's sofubi section.
And click here for ordering instructions in English.
The instructions say they'll only take payment via bank wire transfer. Those fees can be costly, on both ends, and the shopper has to pay for everything. So before ordering, you might want to get some friends together to place a larger order, so you can share those costs.
Of course, Kaiju Blue also ships to Japanese addresses, a process which I imagine is much easier and cheaper.
As always, happy hunting!