Hello!
I have all experience you're need, and already implemented many of Cloud and Local VOIP Systems for Egypt and Gulf companies
And i have many VOIP solutions and we can use the one that match your needs, and i have many resources (DID/SIP Trunk providers and others) that can help us to add value to your VOIP System.
Also i had an very good Experience with TLS protocol, so i can configure your VoIP system to work in Gulf without need to VPN
Kindly, if you are interested about my offer, feel free to contact me to discuss.