Check out McMaster-Carr.com, look at the "tubing" (type it in within their search area). You can basically select the product you need on the right of the screen by each requirement, temperature, color, wall thickness etc.
What you need is Ultra-Clear PFE rated up to 450 degrees and is about $1.50 a foot. A nice bend radius..but there are many others to choose from there. PFE is what I would recommend for chemical durability, temp and abrasion. Can bend in radius as well.
http://www.mcmaster.com/#tubing/=2y3j5d