John:
If the existing bung holes are in good shape then you can just glue new bungs in. Wait until the glue dries and then knock of about 2/3'ds of the exposed bung with a wood chisel. Then take some 60 grit sandpaper glued to a small strip of 1/4" ply etc. and knock the remaining bung down to just flush with the existing teak. Fininsh fairing the area with 120 grit paper the seal with the coating of your choice.
If the holes are in bad shape? Let me know....
Bobby