This is probably in the wrong area and very hard to find, but I'm curious if anyone knows where/how I could purchase JUST the trunk of a BRG 2017 XE?

 

If you mean just the trunk lid, I guess a Jag dealer, Ebay or an aftermarket parts dealer.

 

If you're looking for the trunk lid, an internet search is probably the best approach. A written-off car with sever front end damage would suit, but you are very unlikely to get the colour you want, as you are relying on others misfortune for your part !

Here is a typical offer in the UK. I found it in about 5 seconds

https://www.ebay.co.uk/i/15334155598...iABEgIpgPD_BwE