VPN ports blocked by ISP. Any workaround?

I was using free VPNs (the ones with IP addresses, not Hotspot Shield etc) found on the Internet and I used them to set up a connection on my computer and it worked great. But now my ISP has blocked the VPN ports and none of these VPNs are working anymore. However, browser VPN extensions (such as Hide My Ass, ZenMate etc.) are still working.

So is there any workaround to this to get those VPNs working again? Some way to connect my browser to the VPN servers and not connecting the whole Internet connection to the VPN server.