This project is still in its very early stages. Currently the first version is being designed, and I have done some early experiments with ice bath and boiling bath with another thermocouple amplifier instrument I have (Omega 2175A). 

One thing under consideration is the thermal inertia of the thermocouple itself. We are using this with an oscilloscope, we want the response time to be as fast as possible. The thermal inertia of the thermocouple needs to be as low as possible. In order to achieve this an exposed junction type thermocouple must be used. We don't want a conduction path between our thermocouple junction and our scope, however. This means that the actual sensing circuit must be isolated. This will pose a significant complication in the circuit design.