Thielmann Kegs and I need help....(again)

[stumpwater]

20litre Thielmann made keg with ball valve centre. The beer out and gas in lines are combined through an all in one leaver just like on a full size keg. How are these filled? The one I currently have in my possession came from the Molson Brewery. Let me guess...I can fill it but the equipment will cost as much as my house?