I'm going to be putting up a Comet GP6 UHF/VHF Ground Plane Antenna. It will be chimney mounted to a mast, and the total height is around 40 ft. The upper half of the chimney starts at the first story of the house and stands around 25-30 ft above the roof adding to the extra length of the coax. I already own 80 ft of Tram RG213/U Mil-C-17G and was considering using that (they are split so I would have to use use connectors on them so they can be used together). I also own a 82ft Belden RF400.
I'm not sure what to use or if I should buy something else. I'm also considering installing a feedline choke at the antenna side of the feed line similar to an HF antenna I'm setting up. I know the RF400 would be a better feed line but I was hoping to use it on my HF setup 160m-6m end fed Balun 9:1 unun setup that's 100-120 ft away from my ham shack. Same coax I'd like to use for my G5RV. What would be the best type of feedline to use for the VHF/UHF antenna in this situation?
I do know there are a lot of variables. I will be using both digital & analog. The average distance to repeaters in my area is around 25-30 miles. I'm currently able to hit them with my 50W mobile rig without issue. I'm willing to buy different coax if needed. Leaving out the difficult to determine variables like obstacles (there is only 1 to my north but it has not hindered my contact to repeaters on my mobile in the driveway obstacles don't appear to be an issue). My rig will be a Yaesu FT-991a which runs 50W FTM UHF/VHF. I'm just trying to see if there is a preferable coax for my setup.