Who carries plastic dip tubes?
I have one that is bent, and leaks. A metal tube won't fit in.
I assume you are talking liquid side? If so, I have never run across them. If it is the gas in, then Williams Brewing carries them.
Primary 1: Wee Heavy
Keg 1: Northern Brew #1
Keg 2: 11.11.11
Next Up: Bourbonator
Chicompany has them too. But from what I researched some replacement plastic ones don't fit certain kegs. Seems the best way is to drill the hole bigger and use a standard stainless dip tube.
It is on the gas side.