I know of at least two companies that are trying to build a business out of refurbishing EV battery packs and yes they have already experience refurbishing Leaf packs. I will post the links to the companies when I get a chance. Nissan should also be offering refurbished packs in a few years from Japan plant, so, by the time your 2017 Leaf needs a new battery there should be plenty of companies around that offer refurbished packs.
One thing that really impressed me with Nissan is the 2018 Leaf is hardly a year old and you can already buy a service manual for it. Not that I plan to do any serious work on my 2018 Leaf, at least until it is out of warranty, but it’s nice to know I can get the manual I need to pull it apart if I have to. Doing things like swapping out battery packs gets a lot easier when you can get the manual that tells you how to do it.
One other thing you might want to consider, if you are willing to pay the price for a new battery pack, I have heard that Nissan offers a full 8 year/100,000 mile warranty on the new pack even if the pack is sitting in a ten year old car. That is quite a bit of security for such a large investment. You just have to decide if the car is worth hanging onto for the life of the new pack.
2018 Leaf SL
2015 Ford Fusion Energi Titanium
2007 GMC Envoy XL SLT 4X4