Geared 1.75mm Bowden Feeder for 3D Printer (suitable for Flexible filament)

I've built (and designed) my own Delta Printer, wanting something better than the current crop within my price range. Initially I bought a cheap aluminium feeder - which turned out to be less than ideal! It's main issue was that the filament path was not straight and not guided as it passed through the body. If too much pushing force is applied, the filament buckles and the print is ruined!

On my original (Ultimaker) I printed an iRoberti feeder, which is excellent! However, there didn't