theres should be a rubber bush at the bottom,this can be made with big washers sandwiching some rubber.
Or get some anti vibration mounts off ebay that will want the center hole drilling out.,im buying new ones this week as one of mine is missing.
As for the spacer,get a big washer and file to shape.It should be angled slightly.
All info supplied to me by tazzzman after him giving my 2b sliding pillar the once over.