Hi dawn 1511 and bushbaby
We are about to jet off to Goa for our 9th visit but we spent christmas and new year and sri lanka and loved it.......will def be back next year. Regarding spending money I cant remember exactly but think approx £500 for the 2 of us for the two weeks, we stayed in Bentota and because of the 3hr drive back to the airport we went left the day before and spend day and half at the browns beach.....this is a very nice hotel but we a little more expensive than down in Bentota.
Sri Lanka for us was greener and cleaner than Goa and have pavements

but missing beach shacks,
Im sure if you love Goa your feel the same about Sri Lanka
Enjoy
Regards
Jules