I made me wet and dry mops by gluing some pillow form (urethane) to dowel with contact cement. Then I cut up an old terry cloth towel and sewed strips into a tube. I cut off pieces of the tube, sew one end closed, turn them inside out, and slip them over the foam, tying them at the shaft with some carpet cord.
During shooting, I swab with water. After shooting, I swab with a sopping-wet mop (which shoots water up the vent) with hot water and dish soap. I dry mop to pick up the excess water. I should probably oil the bore but I have not seen any sign of rust.
When the mops get dirty, I cut the string and replace the "sock". One towel gave me enough material for DOZENS of socks!