Hi Joe,
If getting the endcaps, I can recommend bro birdfish's waterproof endcaps - german, good quality and looks like it'll last a lifetime. I believe he still has extras from the last bulk order. More ex at $5 per piece but better for peace of mind cf regular non-waterproof G5 holders.
If you want to order Icecap ballasts, let me know - I'm considering odering some in sooner or later....