Help finding "pin" to secure drive cover

[hubbardg]

Can anyone tell me where to find the pictured part? It's used to secured the collar on the drive cover for my Countyline post hole digger. They are plastic.

 

[joecdeere]

At RK, Tractor Supply etc, they are usually bagged and sold along with the u-joints , yokes and such in the driveshaft/pulley area

 

[hubbardg]

What are they called?