Bastens - We are lucky enough to have one of the LEGO City Train Track Splitter 7996 which is now retired. That being said I wouldn't recommend spending over $250 to buy
Double Crossing Lego Compatible - Etsy
The Modular Track Switch System, Now on Kickstarter! | Brick Model Railroader
Lego City 7996 Double Crossing - Brand New - Railroad Retired Factory Sealed | eBay
Toy A Day: #491a of Year 2 Lego 7996 City Train Rail Crossing
4DBrix - Train
Double Crossover Track : Set 7996-1 | BrickLink
Rare] LEGO 7996 City Train Track Splitter | eBay
Lego City 7996 Double Crossing - Brand New - Railroad Retired Factory Sealed | eBay
Peeron: Train Rail Crossing for RC Trains (#7996-1)
LEGO Trains Double Crossover Track • Set 7996 • SetDB