Best way to iterate through rasters in a model

Right now I'm attempting to iterate through rasters collected in a file geodatabase, in a model that I've created using the model builder in ArcGIS. I don't have the ModelBuilder Toolbox, otherwise this would be a lot simpler to do.

Is there a way (without using the Iterate Rasters tool) that I can loop through the rasters in a gdb?

Thanks,
Renee