i prefer plastic spacers because they compress nicely and somehow it just works. i've put 6k km on my LT268 w an airwolf T1000 cockpit that came with all plastic spacers, and havent had headset play at all, and there's just the right amount of gap. I think any of the plastic spacers set for integrated cabling stuff will work, it's all cheap basic plastic, but it works beautifully. i've built 5 bikes like that.