RSE supports import / export but cannot do incremental upload today. I'd still recommend rsync (or an rsync clone) for your task - there's a couple of options available freely, also for Windows clients or hosts.
For anybody else reading, I was able to get this functionality by installing the aptana studio plugin. Aptana studio allows you to define sites and connection settings that represent a source and a destination. Then it gives shortcuts for uploading a file using a given connection.
It also has the capability to upload on every save with some additional configuration.