Twin front brake lever for straight bars?

[danphoto]

In order to modify the front brakes on my Christiania, I need a brake lever which fits onto straight bars, pulls on two separate brake cables and has a parking brake facility (preferably of the "push button down to lock, squeeze brake lever to release" type).

I believe that such a thing is used on some recumbents, but I haven't a clue where to order one from online.

Any ideas please?

 

[betty swollocks]

here?
For parking brake simply pull lever towards the bar and hook a strong elastic band or old piece of inner tube round.

 

[zexel]

Twin pull with parking brake

 

[danphoto]

Thanks zexel!