Tyga: I Can't Believe It's Not Kylie

Tyga's found himself a fine, fine Kylie Jenner substitute.

Hard to ignore it ... the chick he was with in West Hollywood on Thursday really looks like she could be Kylie's body double. Of course, the question ... is she a Kylie-authorized stand-in or is Tyga staffing up on his own?

She could be a potential singer for his label -- like that 14-year-old girl. If so, at least he's not texting this one. Best to keep it in the open.

As we first reported, KJ and Tyga are giving each other "more space" after their mini-split.

Everyone defines "space" differently.