Hay MG - that's a pretty dang decent Star you got for yourself there. The 9mm Largo is a real decent round to shoot, just shy of the 38 Super power levels. I know that aluminum cased ammo is availble from CCI - got a box of it for my Destroyer Carbine and it's pretty OK, and that reloadable brass is available from Starline.
Since the Largo (meaning large or long) is just a 9mm case, you should be able to reload the brass using 9mm dies, and vice versa. You can also shoot cast loads and my old Lyman manual lists loads for the 9mm and 38 Super cartridges with cast rn bullets up to 160 gn - decent plinking stuff.
BTW, if you ever feel the need to downsize, 9x19 (9mm Luger) barrels are available. Also, you may wish to consider a set of new springs for it from Wolff.
I used to have lots of fun shooting the old Stars, Llamas and Astras in 9mm Largo - I hope ya'll have a blast. Mikey.