Hello, I have finally made my mind to put on some 14" ape hangers

please don't try to sway me

Can someone please tell me where I can buy some extended cables and which ones I would need to change. Thanks in advance!
First, I wouldn’t try to sway you because the more I look at ape hangers, the more I like them. 14” seems like a good size as well. I believe in the correct size they would be more ergonomic and would have minimal to no impact on performance.
There are many places out there that can get you your cables and brakes. I took mine to a local brake shop and had them made up. I recommend you do the same for this reason: you can take your old set in and tell them “it has to be exactly like this, only X inches longer” having measured after installing your handlebars and measuring the difference in length. Of course, you can also specify materials and colors for the new lines. I tried ordering once and got a “custom line” that did not fit. Way easier and not any more expensive to just have a brake shop do it.
As far as the choke and throttle cables, get the length you need and order them from Barnett, or Motion pro. In fact, there are many folks on the web that can make them. I used motion pro for mine and they were perfect.