Franky, I went to a few different places. I replaced all of mine. Here is the places I found the best deal for the Maxxima brand of lights, which had the look and # of leds I was looking for. There are several different styles of each light. The series that my trailer takes along the sides (markers) came in 3-led, 6-led, and 8-led. I liked the look of the 8 smaller leds, so I knew that was the ones I wanted.
Also, for the oval (type-60) STT (stop turn tail) lights, they come in several flavors. Something like; 10-led, 12-led, 23-led, 40-led, 52-led, and 60-led. Again, I liked the 60-led ones that have 3-rows of small bulbs.
Happy shopping for whichever you like.
http://www.superbrightleds.com/
http://www.etruckpart.com/maxxima.htm