That is a Seimitsu LS-32, with SS mounting plate. LS-32 comes with flat RE mounting plate, so you must change. Or you can just use the mounting plates from your current LS-32s. SS plate comes with LS-32-01. Of course, LS-32-01 comes with a PCB, which means it has the 5-pin connector, however, the microswitches are still exposed and can still be used just fine. But I’d save myself a couple bucks, order an LS-32, and then take your existing SS plate off, and then put it on your new stick.
There are only 2 restrictor gates for LS-32, and that is the square one that comes with it, and a round one that must be ordered separately. You can unscrew the existing gate and move it to a different position if you want dedicated 4 or 2 way operation.
Also, you mention Sanwa joystick. If you want Sanwa, then I’d look at JLF-TM-8T(-SK). That means JLF without PCB, and with flat mounting plate. Sanwa sticks have a longer shaft, so generally, an S type plate mounts the shaft too high. But if you want with S mounting plate, get JLF-TM-8S(-SK). -SK just means with shaft cover. That’s up to your preference. LS-32 does not have shaft cover. It is a plastic piece that covers your joystick. It’s mostly aesthetic, but it protects the metal, but if you’re going to just be using it personally, you won’t have to worry about it. Not to mention, the shaft lasts fine without it. It’s just an extra layer of protection in case if the stick is constantly in use by perspiring players. But if you like the black plastic cover, then get it. But once you order, you can’t just take it off. You will have to have a dustwasher for a stick without shaft cover if you want to take it off, because it leaves a large hole where the shaft cover once was.
If you like the restrictor gate of LS-32, you should use the square gate of the JLF, which comes with all models of JLF.