I get my Boeshield T-9 at West Marine or BoatersWorld, but you can get it online at:
http://www.theruststore.com/Boeshield-T-9-12-oz-Aerosol-P3C4.aspx?gclid=CKut5822iJwCFSUMDQod-1bPQA
I've never found anything as good and I been trying for 20 years. I don't think I'd waste any on a knife. The truth is that we have an embarrassment of riches these days where rust preventatives and lubricants are concerned. There must be 25 products that will work fine under all but the most rigorous circumstances--e.g. exposure to salt water, then putting up wet in a leather sheath...
I bought a Ruana 6BD skinner back in 1988 made from 1095. You wouldn't believe what that knife has been through. Once or twice a year I hit it with Flitz, maybe put a bit of A.G.'s rust preventative on it if it is going to sit on a shelf all summer, or maybe a touch of BreakFree. It's never had rust that I can see, but even if it did, it would take about 50 years of ignoring it to make a real difference in its usability.
My little old Schrade gut hook is about the same age, also 1095, and apart from a patina caused by all the blood and acids in animal fats, it works fine with just common sense care.
Use your head a bit, and a 1095 blade should be good for hard use for about 5 or 6 generations. My old man has got a 1095 blade that he's been using since 1945 for every thing under the sun and water. We live alongside Chesapeake Bay in the salt marshes. The whole family has been cutting up fish bait with that thing since the mid-1950s, not to mention digging with it, cutting up rubber and wires, whittling and wood carving, etc. All he's ever done is wash off the salt water with fresh and dry it.
It probably does have some rust on it, but it will still cut a deer's head off or split a sternum. What more could you ask of a knife?
Hell, for that matter, every animal that's walked in North America for the last 20,000 years could be dressed, skinned, and butchered with a piece of broken rock. Rust, Schmust...