I have a 1997 Winnebago Adventure on a 1996 Chevy P-30 Chassis. It has a 454 7.4L L19 V8 engine that needs a new dipstick tube and dipstick; old one broke off. The dipstick tube measures about 50" long from end to end. I have tried to find one online but have been unable to locate one that fits this size engine and is that long. I need help locating an online supplier were I can purchase it. Thanks in advance.