My Colchester Triumph came with both bronze and roller fingers, though I never used the rollers. Industrially all i ever saw was lubrication by lots of oil from the oil can or flood lurication of soluble oil. In order to concentrate on the turning rather than continuously using the oil can, I used a drip feed stationary engine oiler mounted on a bracket and attached to the fixed steady,this kept a regular flow of oil. When working on stationary engine crankshafts which usually have a keyway at each end to drive flywheels or pulleys,I would make up a bush which was a good fit on the shaft and secured by a grubscrew which located in the keyway,this gave a continuous bearing surface for the steady fingers and spanned the keyway.Though I have never had any problems with steadies marking the work,we were told it was more important to make sure the steady was dead in line with the centreline of the lathe,as an out of centre steady will cause the workpiece to "walk" out of the chuck jaws.when using a steady keep an eye on the temperature of the work,if it gets too warm it will expand and put pressure on the steady bearing pads and this expansion can mark the work,