The RN, Polaris, Chevaline and Poseiden

Anyone have any estimates on what moving to Poseiden would have cost compared to developing Chevaline and continuing to support Polaris by ourselves?

There is the wiki article but…

http://en.wikipedia.org/wiki/Chevaline

I don’t have the figures but I remember a documentary somewhere saying that by the 80’s it would of been cheeper to build five new submarines and adopting Poseiden then developing Chaveline.