Does anyone know a site where one can look up prices for seasons from
out of London including travelcard?

The NRE site only offers station to station prices in the season
ticket calculator, and even if you put a London Suburb it just tells
you there's nothing available, rather than offer the travelcard
version (which would normally fit the bill and more).

Calling NRE tends to get variable results for one ticket at a time.

Thanks.