I just got an old Ergodyne EDB 605 5 string bass from my best friend from middle school. I love the 21 year old bass and and functions as it should. The problem is, it is missing the back electronics cover and one EQ (Bass) knob. I'm sure I can replace the knob easy enough but I need the back plate and it is discontinued. I have the part number - 4PT1CEDB2, does anyone think they can help?