There are many many choices out there for lighting a planted aquarium, but finding a light for a riparium can be a problem. First off, some riparium plants (like peace lillys) grow quit tall, so unless you have a very tall tank you are going to need some out of tank space for the plants to grow into. Second, the Rafts and other riparium material will greatly decrease the amount of light getting to the aquatic plants, so having a strong light is a must if you would like aquatic plants. Probably the best way to light a riparium, is to hang a strong light fixture, like a T5HO fixture, above the tank. This can be done many different ways. Some make metal pipe stands that stretch above and over the tank with the light hung by a chain which is attached to the piping, while others attach chains to the ceiling above the tank and then hang the fixture from said chain. Cheap, easily hung T5HO fixtures can be obtained at many online hydroponic stores like Paradigm Gardens.
For lighting my 20gH riparium, (see picture above) I drilled a piece of 2X4 wood into the ceiling. I then drilled two C-hooks on to either side of the wood and attached jack link chain to both hooks. The chain was then attach to the hooks that the manufacturer had added on to either side of the fixture. It doesn’t look the best, but it works!