Where do Grim Reapers get their Cloaks from?

The grim reaper. A cloaked figure, dressed in all black, transcending through realms surrounding life and death, haunting all those in its wake. 

After searching through the internet via Google I have found no means of explanation which tells one about where the grim reaper acquires its attire from. From whence does its cloak come? Has anybody bothered to question its one fashion statement? Do some humans contribute black cloaks to these beings as a form of bargaining so that they may live a little while longer before these beings visit them and take them from their lives and loves? Surely it does not appear from thin air dressed in the way that it is, a neat black cloak covering the lengths it is meant to - perhaps there exists a tailor who creates these cloaks for the price of immortality? 

Perhaps even these beings create their own cloaks. Maybe some reapers reap whilst others sew for those who reap. Maybe even they spawn in that cloak, with one hand carrying a scythe, convenient because they may immediately get to work from the moment of their, if you like, birth. Maybe they inherit their clothing - maybe their time is too up after a certain period of time or after a certain number of reaping and then they pass their clothes onto the next of kin. Maybe the more rustic the cloak, the more ancient and the more experienced it makes the wearer, giving the wearer also a higher reputation earning them more souls to reap than others. 

Grim reapers are too elusive to interview, and that proves problematic because no human can ask it this question. No human thus will ever know where it obtains it's clothing from. And it is worrying because they all conform to one style of clothing which means that there most likely exists a large cohort of grim reapers who each must wear the same things so as to be noticed by another. That also means that the cohort exists, the number within unknown, but may multiply to exceed the number of humans which means that there may be competition between each reaper, which may be the reason behind why humans wage war - maybe they are among us and their cloaks are magical because they transform into that of the president's, or an army lieutenant. 

Either way, it would be of interest to know where their cloaks come from. Maybe they are like Macklemore and they go to the thrift shop to buy our granddads' cloaks.