http://www.donedeal.ie/view/10239441
Not my ad, just sharing as they seem like decent prices.
Would you need a cask to be able to run this set-up?
You can modify your corney but to do this right you will need to cut a piece off the bottom of the dip tube
If you can get soft flexible tubing then you could remove the dip tube and fit the flexible tube with a float on the end of it. Then you are only drawing off beer from the top. The corney being narrow is a possible problem hence the soft flexible tubing. :)
Or you use the trap that you get on the bottom of cheap syphons, or add a piece of rounded tubing that turns up similar to a brolly handle.
Best used with a cask, the taps for corny set ups are cheaper