Go scope around the Classic & Vintage forums for abit & search oxalic acid. It can do some pretty impressive de-rusting. You can get some off ebay for cheap & soak everything to de-rust it, then shoot linseed oil inside the tubes. That looks like a lot of surface rust but it should be salvageable, just . The chrome will be pitted, but you can do a good clean up and ride it.
If you're thinking about rechroming, not sure about that but maybe take it over to a local powdercoater and get their opinion. (also, if you're thinking powdercoat or something, don't do the linseed oil til it comes back)