I don't have any direct experience with dichlorobenzene, but a quick look at Schweitzer's Corrosion Resistance Tables is enlightening. Carbon steel is rated "good" with dichlorobenzene to only about 20 °C. 316L stainless steel is rated "good" up to 44 °C, and Hastelloy C-276 is rated "excellent" up to 165 °C. Based on this limited information it would seem that Alloy C-276 might be a good MOC for your application. C-276 is a nickel, chromium, molybdenum alloy, has exceptional corrosion resistance to many process materials, and is available from multiple suppliers.