I use these and I love them. I have 3. One for UVB and the other 2 for plant lights. They come with the plant light bulb. You can just switch it out for your UVB.
Most are made by the same company; all identical, so shop for price:
36" is sometimes considered an odd size (I have one) and may cost as much as a 48".
Some also come with a 6400K plant bulb. If the price is right, just put the bulb aside.