The saber ending on Jakku seems less likely than ending up in the hands of a barkeep. Maz gets a lot of strangers from all corners of the galaxy passing through her establishment. Someone could have sold her the saber, if only to pay off their tab.
and put it in a very similar box to that what OB1 had in his ‘cave’. I think I actually preferred the leaked idea that the opening shot was a light saber spinning in space and then landing in Jakku (Superman), where Rey is scavenging and notices the impact and goes to investigate.