Anyone may suggest a temperature sensor technology that will work to a max of 200ºC?
Thermocouple will be the cheapest sensor and the most rugged, not necessarily lowest system cost. 

Platinum RTD will likely be the lowest system cost for small quantities and will be quite stable. 

If there is high volume involved (eg. appliance applications), consider a silicon resistive sensor. 

I would not recommend thermistors or semiconductor sensors in this temperature range.