Beedspeed also carries LOTS of harnesses. Here's one that looks like what you're after.
https://www.beedspeed.com/vespa-wiring-loom-px125150200-classic-p-1704.html?osCsid=rchu5jle9tq340u7vc2fet0b60 I'm thinking that this harness might be the same one that I was guessing you'd want from SIP. If you click on the Beedspeed link and open up the page, there's a little PDF icon (that's located right above the item description) that you can click on to see the wiring diagram for the harness....looking at the diagram, it looks like that that's the one for your scoot. The question is, is it the same harness that SIP has?
...and remember, it's only the main harness you get. If you need new a new headlight switch, turn signal (indicator) switch, fuel (benzene) gauge sending unit pigtail extension, front brake light switch, keyed ignition switch, or a speedo to "multi plug" extension harness, those are all separate.