Here's a couple of sites you can check out for reasonable deals on cable:
on ebay, there is often mil-spec silver clad wire with teflon insulation, usually very cheap. Or get some of the shielded silver clad teflon two conductor cable. Neutrik makes a decent inexpensive rca connector or if you feel like spending more, bullet plugs are very good.
Of course, you can purchase many of the higher end commercial IC wires in bulk cable form and you can buy the WBT nextgen connectors. But you'll spend a lot of money and the DIY ICs have no resale value so you might be better off buying commercial cables if you plan to upgrade at some point.
VHaudio sells the pulsar wire in bulk for DIY and has many very good connector options.
I have a few from Blue Jeans Cable. I am not going to proclaim they sound any better or worse than others, but I will say the quality is excellent.
They use very good Belden or Canare cable (your choice) and very good terminations.
If you want a hobby to make cables, OK. But, if you put any value on your time, IMO you can't make a better quality cable for less $.