Yeah, the Star Wars: A New Hope numbers are a bit misleading. Original release looks to have run from May 27, 1977 to April 16, 1978... which is a ridiculously long run to begin with... where it made about $215M. It then got another short release in July of that year, where it brought in $10M+ (only one weekend is tracked in boxofficemojo). It then got another short release in August of 1979, where it pulled in another $7M. Overall, the "original release" - which ran from 1977-1979 - netted $307M (per boxofficemojo's total release numbers).
It then made another $15M in a 1983 release, then another $138M in the special edition release in 1997.
The site also gives an estimated average ticket price by year. Going by the original release and using 1977 average price of $2.23, SW sold about 137M tickets in its initial run. It then sold another 5M in 1983, and then another 30M in 1997.
The Force Awakens has sold approximately 88.7M tickets so far (based on current sales and average ticket price). I'd imagine it will pass Ep. 4's original release of 137M tickets, but probably not its total sales of over 172M.