A strip of 3528 cool white (4000 - 5000K) LEDs that is 5 meters long with power supply and dimmer goes for about $12 on amazon. Search for Guotong. A strip of 5050 cool white LEDs that is 5 meters long with no power supply or dimmer goes for $8.88 on amazon. THe 3528 strip draws about 1.5 amps, the 5050 strip draws a little over 3 amps.
Amazon has a huge variety of choices.