London - how to take a 12 yr old with no zip oyster on bus and tube

[reup]

I'm taking my sons friend out on Saturday & annoyingly he doesn't have a zip oyster. We need to take a bus then a tube. Do I just swipe him at full adult price on my debit card on the bus or can I still buy a travelcard at a newsagent? I think they still do child tickets at the station (so much more than the zip price!)

What do visitors do? I tried googling but the tfl website is not very helpful.

Thanks

Yes, you can still get child travelcards, and it's a better option than having to pay adult prices if you swipe.

You can get visitor Oyster cards (we have them and don't live in London). Do they do a child version that you could get and keep for future occasions?

You have to apply in advance with proof of child's age to get a Zip Oyster.

The turnaround for issue is really fast, but won't come through by Saturday (tomorrow)

Thanks. Can I get a travelcard from a newsagent? I know you used to but that was pre oyster days. We have to get the bus to the tube.

I'm not sure; I think it might be at tube/rail stations only now.