My first thing i tried making with Fusion360.
Some different Versions should fit 8mm and 10mm Led-strips each 15cm and 20cm long.
Photo shows the 20cm/8mm Version. Support is needed on the bars.
The mount can be pushed from the side on the bar, than it is clippable to the V-rails.
Somebody may find it useful ;)
The bar should be printed with support, 2.5mm worked great for me.
Two of the v-slot mounts should be enough.