I'm currently in Laos to pick up my passport at the embassy in Vientiane. All my funds are in Lao Kip. Not Baht.

Do I need to change my Kip into Baht or could I pay the Thai embassy in Laos with Kip?

The Laos Thai Embassy web site states clearly that only Thai Bht are accepted.

http://vientiane.thaiembassy.org/en/consular/visa.php

The Laos Thai Embassy web site states clearly that only Thai Bht are accepted.

http://vientiane.thaiembassy.org/en/consular/visa.php

You can exchange at banks. If memory serves, from walking out the Embassy gate, you would go right, then at the street-intersection another right, then continue down that street a few blocks and there are two banks on the left, across from each other, on an intersecting street at the corner. The Kasikorn bank across from the consulate would not do it, but gave me directions to the others.