I have a 6000 shimano baitrunner on my 7ft rod and it feels fine, they might be slightly big for 6ft Rods but I cant help thinking you will outgrow those pretty quickly and want some longer rods,
The 55 sized custom black would also be good, that has a 15kg drag which would handle the job nicely, the 8k has an 18kg drag and they will handle anything, they might be a good choice for you.