I really like the looks and handling of the Stainless 1895 SBL and the factory ghost ring sites, but hate the rail. Can you remove the rail and leave the ghost site in place? Or would it be cheaper to get a guide gun ghost ring sites and the lever separately?

You can remove the rail, but the rear sight will come with it. But you can buy a stand alone rear ghost sight from XS to match the front.

I will trade a Stand alone XS rear sight for the rail, if interested.

Consider a skinner rear sight also. Not saying they are better than xs ( they are both peep sights) but it is another option.

Kay9Cop has it. Here is one replaced with a scope.

You can also get the 1895STBL, wood instead of laminate but it does not have the rail...
http://grabagun.com/marlin-1895gs-45-70-18-5-ss-big-loop.html