They made 1600 injection motors in mexico and brazil, you may be able to pick up and old system from one of them? If you want after market it will probably need to be tailored as most are for more than stock 1600cc. VW Speedhsop do one but its 42mm throttle bodies each side: http://vwspeedshop.com/product.php?productid=16759&cat=394&page=1 Which I would think is massive overkill for a 1600cc. In the UK there isn't much other options, there are a few in the US.
Nothing simple or cheap. DIY via megasquirt or similar. The more able you are to make or scrounge or repurpose parts of other vehicles the cheaper it gets. The stock Brazilian CIS FI system is a possibility.. if you can find one and bodge it in .. I am about 24 months into that project. Mine is Beetle plus Golf MK1 plus XR3i plus Porsche...
