If I'm reading the parts books correctly, it looks like the upper cowl from the later long-nose 150 would work for you if the nose cap was changed out. I have several of the long-nose upper cowls available.
N18506 C-150L overhaul project N5275G C-310A flying ecological disaster N37BZ fast wrong way 150 N383FM kerosene burning insanity N55HL you bought a what?