I tumble all my titanium scales but make my own media as I find the ceramic triangles etc don't do a lot to titanium.
I use smashed flint. My sister gets me flint nodules from her local beach and I smash it up using an old arbor press and a big hammer. The arbor press goes into a large plastic tub - to catch the pieces and the nodules go under the arbor which is then hit with the hammer. The rack was damaged so the press has no arm - it is basically a guided smashing machine and is quiet good fun.
The relatively large and sharp pieces of flint soon put a nice stonewashed finish on titanium. You have to change the media fairly regular as the edges wear, but it is free