Marzocchis had bladders and pistons. You can by new freon cell shocks from Progressive suspension. They are S&W's just rebranded when Progressive took over the S&W shocks in the 80's. I have seen people buy new Progressives and paint the spring seats yellow and blue like the S&W's were.
https://www.qa1.net/ do the new gas bags but it seems the one you want is sold out everywhere (i just had a look around)
Yep I've done the Progressive to S&W image change twice now. Here's the ones I did recently for my DT1 racer, I did a set for the KX250A5, I think they went to NSW?
I've called all of the Australian outlets for QA1 but none of them have stock, but NZ did, I figured it quicker to take that route.