Hi;
At a prior qth I had great luck with alpha delta. Their dipole for 80 & 40 meter covers all of forty meters and about 100 kc on 80 under 2/1
It is nice in that you don't have to use ladder line and the feed line doesn't have to go straight down. I had no support under the center and it held up fine. You do have to cut the ends of the antenna for the portion of 80 meters you want to use.
Richard