Thanks for the replies. I am taking it then as being:

Oystercard weekly/monthly tickets cannot be purchased on line and then
activated at Surbiton station as it is not on the list of (Underground)
stations that Oyster have nominated as activation points. This needs to be
done at London Underground station.

The best solution is to purchase the Oyster card to request that the ticket
be active from "tomorrow" whilst in the city and then when heading into work
the following morning, I will be able to enter Surbiton station using my new
travel pass on my Oyster card.

I shouldn't have used the phrase "travel card" as this has confused me
because I want to use not Oyster, not the older paper travel cards.

Thanks for you help - let me know if I have still got the wrong end of the
stick.

M.