Here is a photo of that fitting on Sparky. I believe it year correct as the engine is original to the truck, but rebuilt by the previous owner. Note the short curved pipe has a short length of rubber hose, which for now is plugged to keep insects etc out. As for part source, I would try looking at any plumbing supply store to find something usable.
Thank you. Does 1/4 barb sound and look correct to you?
