Sewer pipe?

Other thread you mentioned black so its ABS. Available just about any hardware store, big box store etc. ((ABS dwv pipe sizes). T/C generaly 1 1/2" on the gray water lines, (though a few use less common 1 1/4"), and 3" on the black water. Typically SCH 40 used and what youll find in off the shelf 'sewer' ABS pipe & fittings.
Lowes I believe sells pipe in less than 10' lengths.