Diesel Bombers - Clutch for a '93 Cummins with a '97 NV4500

I have a '93 Cummins that Im converting from an automatic to a manual using a NV4500 out of a 97 truck. The old clutch that came with the transmission measures 12.25" approximately. Im currently running a stock motor and setup (or as far as I know its stock, Ive had it for just under a year) but I plan on increasing the power in the next couple years but I only plan on going to around 600 ft/lbs, and I doubt ill ever exceed 900 or 1000 ft/lbs and if I go that far I can replace the clutch if need be. Im looking for a clutch that will hold to some good towing (up to about 13,000lbs trailer weight) on a regular basis and I tow in the mountains. This truck will probably never see the sight of competition but I tow a lot. What's the best clutch I can get for that purpose and on a college student like budget? If possible, the sooner the better, I have the truck on the lift getting the old automatic out as we speak and the new tranny should be ready to go in early next week. Its not a super huge hurry because I have some gaskets, U joints, and stuff to change until it gets here and another truck to work on in the meantime but as soon as I can get it back on the road the better.