Hi,
A search block would be of course very welcome!
In the meantime, I just managed to make one from scratch, inspecting the Gutenberg block.
It seems to do the trick 
Just setup your search results template and you’re done!
So here is my setup:
- div (change tag to form and add attributes below)
-- button (icon and no text, change tag to button and add attributes below)
-- input (add attributes below)
Form attributes:
Button attributes:
Input attributes:
