You should check out this site: http://www.arietearms.com/
He/they are making mounts with accessories for all sorts of pistols that do not have rails.
Dan at Ariete Arms is making me a magnetic laser sight for my Ruger P95.
Prices are very reasonable.
At this time (03/16/2013) there is not an option on the web site to just order the mount and
laser for a Ruger P95 (they have the option for a P89 ... but that one won't work on
the P95). But if you send an email and tell them what you want you will get a response almost
immediately (at least that was my experience) ... and (since he has already made one) your mount
and laser should be available to you right away.
This looks to be an awesome solution ... if it is not, I will let you know.