You know the insulators for mounting TO220 devices, the gray plastic sheet thingies, well, you can buy that stuff by the sheet, usually 12 inches square. I've got some at work, which I bought from Farnell, so it wasn't cheap. But, if you had that, you could build your lamp around an aluminium tube. Or, just use the little TO220 insulators to cover up the exposed pads on the back of your strip. More fiddly though.
As an aside, I was going to say, if you want something as bright as a CFL, just use a CFL. A couple of years ago, in the user diaries, I described an inverter using an SG3525, and a transformer salvaged from a PC power supply. It outputs 240 volts DC, which our Australian 240 Vac cfl's run just fine on. I've got half a dozen of them here ready to go, if my builder ever gets my shed up.
Amanda