CR-10 Frame brace bracket

Not big or clever, just an angle bracket to allow rods or bars to brace the 'goalpost' gantry. They have a V on the back that fits the groove in the rails so are solidly located. Both holes are 5mm and just remove the end covers and slide a 5mm bolt into the groove and tighten up, no need to modify the bolt. Bars can be anything (I had a bit of old pergola frame) drilled at 6mm to allow a bit of play, no need to tension the gantry just lock it where it is, hence no adjustment just tighten the end bolts.
I may change to someting more elegant than the pergola bits perhaps aluminium bar with drilled ends ?