Attenuation

I've had spotty internet service for a long time, really always.  I went to pure streaming this weekend and so far the results are less than desired.  I don't have any RF meter equipment but I would bet my soul on the problem being attenuation.  Part of it is due to the service cable from the drop.  It's got that extra thick orange cable, but they ran it all the way around the back of my house to the end furthest from the drop which is probably close to 200 feet.  Then the installer used previous Direct TV distributions and hacked them into a literal mess on the exterior of the house.  There are exposed connectors everywhere and lines that are abandoned.  Plus the dog gone cable that goes to the other end of the house probably runs another 100 feet due to it being mounted on the exterior.   I've checked the connectors for loose points where I can get to them and found a few that had worked loose.   Got a small improvement out of the apparent signal strength out of my effort.  I've got a roll of high quality RG59 which I'm gonna run through the attic to new keystone receptacles where needed, but I'm really frazzled about this service drop length which really was unecessary since my basement is not finished.  I want to cut that drop at about 90-100 feet and bring it in the other end.  Unfortunately, I have no BNC fittings for that thickness of cable.  I've looked on line with no success so far and I can't find any labeling on the exposed end of the cable.  Anyone know where I can get high quality compression fittings for it?  Again, it's extra thick orange, probably triple shield and maybe close to 1/2 inch thick.