Yeah, these signs are non-standard. It was a difficult one to solve. I used a dead end sign for the not a through street, since they're equivalent. I used a "no u turn sign" in combination with an "ahead" sign by using a comma.

These resources may be helpful to you in the future:
https://wiki.openstreetmap.org/wiki/Key:traffic_sign
https://dot.ca.gov/-/media/dot-media/programs/safety-programs/documents/signs/ca-sign-chart-2014-rev3-a11y.pdf