It is possible to swap out the stereo and speakers, although you may lose some of the features such as the backup camera. It might be something worth looking into, although in that case you probably would be better off dropping down to an S.
Just as a follow-up, I looked into it more and it does look like you can swap out the stereo. With proper adapters you should be able to maintain all functionality including backup camera, etc. I intend to eventually do this with my own Leaf, but probably not until I have some more free time.
I don't think you want to do that.
Buying an OEM headunit w/nav is VERY expensive. The OEM head unit on an SV or SL has the nav and integration w/the climate control and various EV specific displays (e.g. stuff via the Zero Emissions button). Swap it to a non-Leaf one and there goes all of that.
I'm not sure what you're trying to achieve.
OP: What are your daily driving needs in terms of miles? How much city vs. highway? Will you have the ability to charge at your work/destinations?
I think Sage is asking where the vehicle in question has resided. See via Carfax and/or Autocheck. Having resided in hot climates = greater capacity loss. And, if it's from a hot climate w/all 12 capacity bars showing, it's possible it's the victim of a BMS reset and didn't actually have all 12.