Looks to be Murray built, probably a junior model without canti bars. Could be anywhere from '58 to the 70s without any morre info, like a badge pic. ~Adam
I was going to say Murray just because of the chain ring, but I've seen the same style on some other bikes, who knows what is original on some of these listings.....
It's craigslist, offer $20 and see if they go for it. Sometimes they'll take a low bid just to get rid of it, as long as it isn't too low.
ironically enough, i see the same murray chainring style but on a cottered 3piece platform on my 67' western flyer 3 speed. not just kinda similar but the same. go figure. neat cruiser though, but looks more modern than 50's. just a bit.