Continuing the discussion from Tiki Wiki Module Upgrade:
In this case, you can try Google Compute Engine or Amazon Web Services. In the case of Google Compute Engine, you can get an instance with 1.7GB memory and 30GB hard drive for little less than $15, which should be enough.
If you expect a lot of traffic, you can get an instance with 3.75GB memory and the same disk space for little more than $25.
You can go and check out the Bitnami Launchpad for Google Cloud Engine, which is free and won't require spending anything more than the cost of the instance usage.
Note that if you launch the LAMP stack, you will be able to install modules on top of it with the applications you specified (with the exception of OpenSIS).
Let us know if you have any additional question or concern.