My advice would be to buy your adaptor and UV/IR filter separately.
You'll get better quality with something like a Baader UV/IR cut filter which screws into the front of your ToUcam adaptor.
That seems a fair price for the 900NC.
http://myastroshop.com.au/products/d...asp?id=MAS-123
Shop around, though. You can pick up the Baader for cheaper than $110.
Be sure to buy an adaptor which has a thread to accept 1.25" filters