Perhaps fluorescent tubes do not work quite as well as the real SAD lamps, but I strongly suspect they are well worth a try, especially if you can use recycled fluorescents. I know you can get special tubes for horticultural use. Plants think they are a good substitute for the sun, so they may work. A cheap way round it might be to work as a caretaker at your friendly local indoor cannabis farm!
Joking apart, SAD is no laughing matter to the thousands if sufferers, and although I have not been diagnosed as such, it definitely effects me. We do not all enjoy the benefit of foreign travel, so we must make the best use of what we have. Spend as many hours of the daylight outdoors as you can manage. If you work indoors, get outside at lunchtime. Get plenty of gentle exercise, walking, biking and ebiking. Do not use bad weather as an excuse, wear suitable suitable clothes. Visit the woods and the fields, even if the trees are bare. Treat yourself to a change of scenery now and then. Take or ride your bike to a different town or area, and ride there for a change. Before you know it, the winter solstice will be upon us, and we shall move, albeit slowly at first, out of the land of shadows.