if you don't already have either the 10-100 or 30-110:
if you want a nikkor 30-110 for ~$120 shipped, it should provide ~300mm relative to full frame (2.7x crop factor).
That's usually sufficient for most things, except birds. Though I believe rainforests are usually pretty dense, making the longer distance shots less frequent.
The 1 mount lenses are ridiculously light, making them great for travel
most telephoto zooms are close to 400g or ~1lb in weight, whereas the 30-110 there is ~175g or ~1/3lb (all the glass required for larger sensors and aperatures)
Many on this forum say nikon refurbs are supposedly better than new, since new lenses don't all get checked over for problems.
adorama is a great etailer too.
The 70-300mm might be tough to hand hold, given it would be 810mm relative to full frame, and doesn't have VR (vibration reduction), and rainforests are pretty shady places. So you'll either have to bump up the ISO, or bring a tripod/flash (is flash allowed?) in order to get steady shots without VR.
a dpreview thread on nikon rainforest gear (not the nikon 1 though; nikon aps-c is 1.5x crop factor)