Softbox Light Kit using a 8½" Heat Lamp Reflector
Build you own Softbox Light Kit with an aluminium reflector from an heat/clamp light and a studio umbrella to help focused light in area you need. You can screw in on top of a Tripod Ball Head with the 3/8" thread (bottom) or clip it on a Arca Swiss Stand Quick Release Plate.
You can buy a common clamp light with an 8.5 in aluminium reflector at your local hardware store, or on Amazon.
You also need a bulb and and studio umbrella.