This will be a very hard design - your relative bandwidth is approx. 1% meaning that you'll need good resonators:
* Tuned to the correct center frequency
* Very good Q-factor (>400)
And 60 dB at +/- 50 MHz is simply impossible; you would need a very high filter order.
The only technology that could result in this sort of suppression is SAW (don't know if it can be done at 1.8GHz). But then the insertion loss would be very high, up to 20dB or so.
I think there's something wrong with your specs. Why not use a superhet, mix down to a lower IF and filter there? The filter will be much easier to implement and on top you'll have frequency selectivity.