See if you can find a friend in the alarm, security, or home automation business and see if they buy from a distro called ADI.
My latest flyer from ADI shows Honeywell brand banana-peel style 2xRG6QS & 2xCAT5E cable at around $230 for a 500ft roll, on sale this month, for almost 50% off their regular wholesale price. It is the style where all four cables are fused together, kind of like twin-lead or clear speaker wire. This is a steal of a deal. And Honeywell makes some of the best cable in the business.
I plan on finishing my basement in another year or two, and at that price, I was tempted to buy a few rolls myself and throw it in storage for the time being.
I used their next-up version which has a green jacket surrounding the 4 cables, just for added protection, and I paid more than that a few years ago, when I built my home (and before copper hit the roof!). I used 3 rolls, and it wasn't cheap. I think I paid almost $400/roll wholesale back then. But now that it is done, it was the best money I spent. The banana peel version is the same cables, less the green overall jacket. Not really needed, but it did offer me some insurance against the drywall installers.
If you have some sort of business license, you could go and open up an ADI accound yourself. Check out their web site adilink dot com, and there should be a list of locations. They have locations all over NY, NJ, and CT, as well as the entire US.
Worst case, if you wanted to, and it was cost-advantagous (is that a word?) I could sell you a few rolls for a small markup to cover my gas and troubles to pick them up and meet you somewhere. PM me if you can't get it easily yourself and need help.