I hope this doesn't turn into another tired thread of just "biging up" the plays for the major DJ's of the 70s/80s. There can also be a big divergence between rarest, most valuable or sought after. Garry Cape had stock of Earl White Jr, and I had multiple friends phoning up over the next week asking and getting copies. There are also quite a few records posted that are owned by quite a lot of DJ's and collectors, with Melvin Moore being one of them, but i agree, that getting an original has always been tough.
The evolution of the internet has brought to light that many records were not as rare as they were once thought to be.