mine broke off when I took my valve cover off. It still stays in place though and it has been several months since it happened. Im pretty sure you will be fine. If you really want them replaced, I guess you can try your local auto parts store for some identical clamps.
They have those little clips at auto parts stores. Mine broke the other day, plastic doesn't hold up well after years of being on top of an engine. The wire loom stays in place on my car though, so I just left it.