[LMH]

Now that's interesting! Back up a little first though. The original Eelco fuel elbows as used on the Cobra's Carter fuel pump have 1/8” NPT thread. I have one of those. The other two I have also have 1/8” NPT thread but the script faces the other direction, the same as the ones you bought. However, the ones you bought look to be flare fittings and larger than 1/8”. 3/8" flare maybe?
Sorry to be the bearer of bad news but those won't even thread into the fuel pump.
They could be valuable for some other application though, I just don't know what it is. Maybe some searching around might yield some info. They're not what was used used on original Cobras but maybe some other car. I don't think I'd put them around my neck just yet! Maybe after some research!
Larry