is there any way to set up a masternode on amazon aws?
Yes, I have one running there which is free for a year with their EC2 free tier service, at least for the first VPS if you're not already using EC2. The instructions are almost the same as the masternode setup walkthrough that uses Vultr as an example. The changes to those instructions are:
1. The provisioning of the VPS of course has a different interface, just choose the same size and version of Ubuntu listed in the masternode guide, pretty straightforward.
2. Logging on to the server is a bit different, since AWS requires you to use their SSH private key instead of providing a root password like Vultr does. AWS gives pretty good instructions on how to download the private key and connect with it when you click their Connect button.
3. Since you connect as the ubuntu user instead of root, put sudo in front of all of the commands--the instructions for Vultr only put it in front of some of them. Also, IIRC, when I ran the 'phored -daemon' command to launch the masternode, I had to use 'sudo ./phored -daemon' instead.
4. The firewall configuration (ufw commands) has to also be applied in the AWS interface by adding the same ports (22 and 11771 TCP) to a security group and applying the security group to the server. If you have a static IP on your PC you can restrict SSH to just your IP address, or you can set it to allow SSH from any IP address. For 11771 you would want to allow that from any IP address, just like the firewall configuration in the guide.
5. On AWS, the external IP address is not one of the ethernet addresses on the server as they have internal network addresses, which requires a modification in the masternode phore.conf file. First, type the command 'sudo ifconfig -a' to get the outward facing IP address (not 127.0.0.1--the other one), and use that address on the bind= line in phore.conf on the VPS. The other lines still use the external IP address shown in the AWS control panel.
Otherwise it follows the same steps in the guide and worked flawlessly for me. Hope that helps!