Are you doing a screen-accurate saber or like in the picture?
In the "I see you have constructed a new lightsaber" scene, the saber had simply 3mm brass L-bar on the sides of the circuit board.
Later in the production, they reworked the assembly to make the circuit board glide on rails over some electronics inside. They put grey T-bars inside the L-bars.
I wanted the first version, so I got some 3mm brass L-bar from
Wentzels in Stockholm.
Instead of T-bars, some builders of this saber have used flat piece of metal or plastic to raise the circuit board.
I think also that brass U-bar could be a sturdier alternative to L+T bar -- if the circuit board fits. Then add the grey line with paint.
However.. while the original circuit board was blue with gold-plating, JD's is a piece of copper with black lines -- and then the colors of the metals clash.
I am not so sure that model train hobby stores have
copper bars of the correct dimensions in stock.