If you want to use a 'walk up' consulate in Lao to apply for a visa you need to use the one in Savannakhet Lao (across the river from Mukdahan Province Thailand)
They still have openings until they switch over to the eVisa system on the 20th of Dec
remember they ONLY show 2 weeks of appts at a time, so at 12:01am the next day comes up for appt (two weeks out)
Here's the savannakhet online appt booking
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