Is a new set of birds necessary if a metzora brings them and then finds another mark of tzaraat before he is able to bring his offerings: Keritot 9b
Linking the laws of the metzora's bird offerings with the laws of the eglah arufah and the sair hamishtaleiach [scapegoat], because all of these are brought outside the Beit haMikdash: Keritot 25a