They might not have a 116719 BLRO or 116619LB in stock at your chosen AD, but either would be sent out in a day or two for a customer wanting one.
Just among the few thousand of us here on tz, there is a discretionary discount which AD's are allowed to give on higher value models. You may be able to exceed that if you buy an unworn watch from Europe, which with sums of £20k or more could be a worthwhile saving.
Haywood