To Coop in Dark Souls you just have to be in soul level range, it doesnt matter what NG you on. I've only got characters at SL45 & SL15. But I could do bottomless box glitch to give you weapons on new characters if you need help? NG++ isnt easy for most of people.
Dont level up your Character on Darks Souls to ~SL45. What level are you currently and what weapons do you need? I could just create a new character and get to your level to help by dropping the items for you. I be free tomorrow to do this if you like.