Idea for a 8 channel switch/sensor (flush mount)?

Hi, i want to have a cheaper solution for this:
8-channel knx sensor

Any idea how i can get something like this in a cheaper way? This knx sensor costs about 100 euros.

The type of switch/sensor doesn´t matter. I have flush mounts and i can get 230V as well as voltages between 5v and 48v. I have knx wires in this place also.

I think this is the MDT switch here, correct ?
In my opinion it is not worth spending the time to look for an alternative if you already have the knx wires available in that place. Just saw an offer in the bay for the KNX BE-TA5508.01 - roughly 85€ including shipping.

Maybe this? http://shop.haus-bus.de/controller.php?setType=produkt&setValue=10464

German only.