On V8 powered 2010-13s the HD option won't be that easy to find (whether you pick Lux or non Lux should make little difference as the Heavy Duty pack was a self standing option on every trim), I had to special order mine from the UK in late 2012 because my dealer couldn't find a single one fitted with it in the Western US. If you have to settle for a 2010-13 V8 without HD, at least you know you'll only be giving up the electronic locking rear diff and a full size spare wheel.
On 2014-16s with the SCV6 engine however, no HD pack means no 2-speed transfer case AND no rear loclers, so the lack of HD should be a definite deal breaker (if you enjoy wheeling your Land Rovet regularly, of course.)
This - I had to search high and low to find one as I missed the cutoff to order one. turned out a dealer in NM had three, had to get one shipped to GA...