Thanks!

I had found the S/N page, but not the manual, and IPD page.

This is the manual that I havehttp://www.crosman.com/pdf/manuals/BC9CB9-OMSV.pdf

But, after the last page shown, there is a "NOTES" page and then the page after that is/was a registration form, that says "CUT ALONG DOTTED LINE" and Form #438 9/92.

The C9 1995 soldered valve IPDhttp://www.crosman.com/pdf/manuals/BC9-SV-EVP%20&%20PL.pdf
is closest. But the spring (P/N 766-091) is not installed, and there is not a place for it to be installed, in my rifle.