I am new to this hobby and some of the prices just seem like an extortion to me. Since I don't know how much I want to invest in the future and soon I will be able to test my diving photography in Palau, I wanted to use some cheap solution for tray and handles. On the market the cheapest trays cost more than a €100 and moreover I have to order them through Internet. Thus I decided to make my own, which costed me less than 10 euros.
All the solutions I found in internet use PVC pipes, which are bulky and since I am flying I will not have so much space in my suitcase.
My camera, dome and case weight approximately 3 kilograms.
I bought 1 meter galvanized aluminium stick, with 25mmх2mm ( width, thickness) - from the nearby hardware store it costs around €1.50. I bought 0.5 meter pipe for handles - €2.
Then I drilled two holes with 6.5mm drill, very slightly bigger than the tripod hole.
Then I cut the extra lenght of the aluminium rod and curved it.
I put the pipe over it, it strengthens the grip
And I finally filled the pipe with polyurethane foam for the pipe not to slip, as well for the better buoyancy, because of the trapped air inside.
The end solution is the following:
I hope that helps to the people who don't want to spend thousands of euros in gear.