You could take it to a sandblaster, but it might blow through some of the rust pits. If so, you could use Bondo to refill those holes as long as they are not in a 'structural' part. The other way is to sand by hand. I have refinished several ( not for individuals ) and it can be time consuming. You might want to check with an auto refinisher / restoration person. I have seen people get them painted with auto paint & some get them powdered coated. I always used a spray gun with oil based enamel.

Here are some I've done in the past - no longer doing this, so please don't take this link as spam. I'm only showing it so that you can see there is life after rust. Most of these were in rough condition when I got them.

Also - if your swing arms are bad, you might be able to get a local metal shop to make you some new ones since there aren't any parts available for these old beauties. We used to keep a 'stock' of old ones to try to get parts from.

I hope this helps!

Here is a link that might be useful: chair's I've redone

anything is salvageable with enough effort. However, if you dont want to put a whole lot of effort into this thing you can just knock the loose rust off with a wire brush (a cup wheel in a cheap angle grinder is great for this), brush or spray on a "rust converter" (loctite makes this, its available at farm stores and gemplers.com under their own brand) and cover it with an _oil-based_ topcoat. shouldn't take more than a couple of hours tops, and it will help preserve it is case you ever do want to take the time to do it right