Dog toy timed release thingy when not there, where ?????

[Tampon]

I leave my Lab for about 4-5 hours 3 times a week, he get a walk and swim at the local woodland/lake before and has a meal and a few toys with the radio on when I leave. When I get back is fine and we go for walk in the park but I would like to keep him better entertained. I know he eats then goes to the treat toy then just goes for a nap for a couple of hours.

I have a few toys, treat toys and motion activated noise ones etc. What I would like to do is leave him his meal and hide a few treats around the house as I do now but put one or two treat toys in/on a machine that will drop them 2 or 3hrs into the time his is alone.

I have found this http://www.petgadgets.com/product_details.cfm?prod... but it is only for Kong treats, is over £100 and they stopped making it. Also there isn't really a option to put different types of toys in it.

Does anyone know of anything like what I am describing, I think I will have to make something but would rather the place didn't have a heath robinson contraption in the kitchen.

Any help or tips you have gratefully received, even if they aren;t about the contraption and are ideas of keeping him entertained.