I don't know if you've ever heard of Baker Creek Heirloom Seeds, but they have a whole selection of winter squash. They might have some varieties that would perform better in your climate if you find you have trouble with the varieties you're trying to grow. I'm not affiliated with them in any way. I just happen to use them almost exclusively for my seed purchases so I know they have a wide selection of what can be harder to find varieties of stuff. And I'm pretty sure they ship internationally. http://www.rareseeds.com/