Ok, so I’m using these (see attached picture) 90 degree angles on my robot but recently it was brought to my attention that they actually aren’t legal as they aren’t sold by Vex and they aren’t mentioned in R7 as a “non-Vex” component.
My question is if these are legal or not to use in VRC. Thanks in advance 
Correct. If a part is not sold by VEX Robotics or covered as an exception in rule R7, then it is not legal for use in the VEX Robotics Competition.