The 150-4C went out of production before the advent of Thiele-Small parameters. Somebody may have determined the Thiele-Small parameters in recent years, but you can't rely on somebody else's measurements, because after all these years, different 150-4Cs will have widely different parameters. That is, you will have to determine the parameters for every 150-4C you plan to use. This is hardly the way to go.
The Italian company Faital Pro has two 15" woofers that fit your bill:
15FH510:
http://bit.ly/VUrVzW
15PR400:
http://bit.ly/V5a2h5
Other members will have different suggestions, and modern drivers will in general be a better choice.