Looking for non squared Hub/carriage bolts maker / source

[JBrennand]

I have a 1920 Cleveland which has 7/16 hub bolts/carriage bolts. They do not have a square fitting like most carriage bolts rather a larger round head. Anybody here have a contact or company for such a bolt? We just had the wheels remade by Calimer’s Wheel Shop in PA. the original Wheels had a mixture of the original hub/carriage bolts and then some modern hex bolts. We’d like to return them to the originals but obviously not many places make the non squared carriage bolts. Any sites / makers out there you can refer me too? Thank you. 

[37_Roadmaster_C]

If you can not find a source another option would be to find a standard carriage bolt with the closest head and then having a local machinist turn the square off the shank and even turn down the shank and rethread if needed to make them proper. This would be a very simple matter with a lathe and a small bit of time....

[ArticiferTom]

What anchors it to hub from turning ?

[Mark Shaw]

Most vehicle manufacturers used wheels from other vendors. 

Look closely at the wheel/rim and lugs to see if there is a manufacturer stamp to ID the wheels. 

Then post photos and ID so the correct wheel bolts can then be found. 

[auburnseeker]

Post a picture of one if you can.  I have a few drawers full of NOS hub bolts from a long closed parts store that opened in the teens.