Honestly, no I hadn't thought of doing that at all. I'd only looked at the 5 or so engines available on ebay motors to get an estimate on a price. I'm going to reach out to the mini dealership near me to see if they can do a better price and I'll look into what it takes to get one imported as I have no clue how to even start approaching something like that.
As for resale value, I don't think that is really playing into this anymore, firstly because I just can't get a good comparison the only other 2014 paceman JCW we can find is for private sale for $18k right now. Mostly though because after talking about this more with the wife, she just really likes her car and even though I've offered to get her a nicer and newer car she seems pretty hesitant still and asked me to look more into getting it fixed.
I really appreciate the suggestion for importing an engine, I would never have thought to look into that!