Progress OE 11.5 License models

I need to buy OE 11.5 license for developing a solution where progress 4GL acts as a middle-ware.

I have a web based UI which communicated with progress application server and request's coming from UI processed on application server agents. Also I am using Oracle as database, so need data server license also.

I checked progress licensing models and I am confused a bit. Consider for PRODUCTION environment I would be using one Linux server having 2 application brokers with 25 agents each. Will also have 4-5 background batch processes.

Request coming on application server's will be coming from external Web/Java based applications. Application broker will be using Oracle data server to connect to Oracle. User names across both servers will be same.

Now I am confused about which License model I should go and what should be limit on users/processes in license.