Flat headed carriage bolts with clip

Wanted to buy:
Three of these carriage bolts with a clip to locate them in a slot. Thread measures 1/4-20, but square part of bolt is smaller than normal 1/4-20 carriage bolt.
Used in dash for radio and speaker mounting on 1968 Barracuda and probably several other Mopars from the era.
Please respond with price and payment terms in a PM. Shipping to North Greece (Rochester) NY 14515.
Thanks!

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