150mm CF. The C lenses have the aperture and shutter speed locked together unless you depress a lever. A real PITA. Keep an eye on KEH.com for a CF. I got a "bargain" rated lens from them for $565 and to this day cannot figure out why it was rated as such. There was some MINOR brassing around the lenshood bayonet lugs, but the appearance, shutter and glass are otherwise flawless. And it comes with a 10 day return period with no questions asked. They also have some sort of warranty, I believe, but I've never needed it.
Of course, the nicest HBlad portrait lens is the 110/2 that can only be used on the focal plane shutter (F) series. The 150 is the most popular lens used by portrait studios. The 120 and 180 will be slightly sharper than the 150, but sharpness is not always what you want for portraits anyway. The chrome lenses are fine, especially for portraits, if you can live with the linked shutter speed/aperture and sharp knurled metal rings. Also, HBlad doesn't stock parts for the chrome lenses anymore (but there are thousands of dead ones to scrounge from). The later C lenses were made with the T* coating - they were also made concurrently in black chrome - and are marked with a red "T*" on the barrel. Considering how cheap HB lenses are these days, aim for the CF series... INMO the mid 1980s were the peak, and they the quality went downhill in the mid-1990s.
Also, HBlad doesn't stock parts for the chrome lenses anymore.
Asked Hasselblad about this issue last summer: all parts for C-lenses were still available except aperture (sic!) blades, pc-sockets and contacts and some front-lenses. Doesn't sound too bad 25 years after they stopped making them. I would always take that small risk instead of not being able to shoot because I could not afford a CF.
On topic: The 150mm works well for a range of subjects including portraits, is compact and available for moderate prices. You'll like it!