You might actually try a local Ford dealer. Since you have the number you never know, they may have some still.
Otherwise be sure to ask whoever you're looking at that has them to use USPS instead of UPS or other setup. Then again, if they're like us and do everything through a pre-programmed computer, it probably categorizes it as "boxed" and our guys can't just throw it in an envelope and put a stamp on it. Sometimes I long for the "good old days" in that regard.
I'd suggest a local NAPA, but frankly that clip is just specialized enough that it might be a hard one to find locally other than a dealer.
But you never know, so don't overlook them at least for a quick try.
Good luck.
Paul