Non-standard diameter pole - reinforcing a repair
One option might be to make yourself an ABS slurry by dissolving a sacrificial part of the desired color in Acetone:



This should be able to bond chemically with the ABS parts for a strong connection, and you'll have extra plastic material to work with, so you should even be able to make it stronger than the original design by building up the area slightly if desired.

You might want to practice on some other broken parts first to make sure that this works the way you expect.