So book a flight out and go back get the extension and cancel it, (it's not rocket surgery or brain science ๐ ) They're wanting to see that you're going to leave in 60 days.
NOPE, you cannot just fly in to the Lao city of Vientiane, show up at the consulate and BUY a tourist visa ๐
You need to make an appointment before you go to apply or you can't get in the gate, and you need to meet the requirements to apply or they won't accept your application.
This is the info on a tourist visa for the thai consulate in Vientiane
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