Up for grabs is a Migsel type triple RAM ball mount for an ST1300. I've always thought this was a Migsel made product, but can't find it on the Migsel website. The closest they have is on the below link.
https://www.migsel.com/store/index.php?_a=viewProd&productId=49.The Migsel price at around $300 shipped from the UK, is pretty scary, but
this can be yours for $100 (posted to anywhere in Australia).
Anyways, this mounts on the top of the ST1300 dashboard. It's an easy fit, probably around an hour, but be patient and careful with the removal of the plastic panel / fairing clips.