I just got one in an order placed a month ago. I know you can find unfilled bullets on sites like AliExpress (direct from China) or even Amazon (might be faster shipping but cost more).

I only got the one and it’s useful but it was packed pretty tightly.  Had to take some out and stir before it worked well enough for my purpose. Might just be the type, since the other toast type I have doesn’t really announce itself.