I also live downtown and I'm high risk right now with a serious conviction.. You oughta be able to do a bit better but not much. I'm a few years younger than you but I've had my G for a long time and have just gotten my M2 again in December when I got my policy, I ended up insuring my Honda C70, they wanted 3k+ for a 74' CB125 or a new Gromm. I said f*** it. Get your license, take the course, shop around as much as you can, practice riding as much as you can, keep your record clean and either bite the bullet and drop a stack or two apparently on insurance for the vespa or something even smaller so you can start building your driving/insurance record or go back at it next season..
ps. the vespa could be steep for coverage because of a high claim rate/replacement value? maybe try a comparable old Honda? lol