Under-ConScript Unicode Registry
UCSUR is the "Under-ConScript Unicode Registry." It attempts to standardize the unicode codepoints in the Private Use Area for constructed scripts that wouldn't be accepted in Unicode.
sitelen pona
sitelen pona has a USCUR specification
There are instructions for making sitelen pona UCSUR work on your computer
nimi Linku has a list of fonts with information about what they support
Web-based text converters exist
Defined codepoints (2022-05-20)
Note that these will render as "missing glyph" boxes unless you have a UCSUR-compatible font installed
pu:
ku suli:
ku lili:
special characters: