You need pvc paint not Hypalon they are very different!
Go with superflex by (polymarine) its specifically for pvc tubes
They also do a range of colours ie. The most common rib types orange, black etc...
It's pricey stuff around 38quid 500ml coverage 2.5 msq
Put it on with a gloss roller DIY radiator size and cut in with brush
It drys quite quickly allowing you to build up decent layers
You'll rarely get sun damage breaking down Hypalon
Pvc gets attacked by the sun easily where Hypalon is uv resistant hence the price difference in material and rib types
Hope this helps