Hello…I have a septic tank made out of concrete, but doesnt have a riser. Can I purchase a PVC riser, somewhere, and install it myself? Concrete is cheaper I know, but I live and work alone…would be hard to install, would rather pay for the PVC. Is it something I can find, somewhere, and something I can handle by myself? Otherwise, any other creative solutions akin to using old metal trashcans or car parts?