Since you're out of warranty, Nissan will most likely do nothing about it. 8K over a 60K warranty isn't a tad bit; it's a world of difference.
Anyways, these VQ37 motors can be had all day long for under $3,000 on Ebay or other reputable Japanese engine dealers. Be different, go VK56
be like that drift 370. I would if I was in the same situation as you. Hell, contact Hinson and see if they offer an LS swap for 370s.