@Ste***
, "there is no such thing as a marriage visa" :/ you already hold a 90 day Non-O visa based on marriage to a thai. Your next step would have been apply for a yearly extension of stay by meeting the financial requirements.
Why not take the 60 day extension of stay I recommended from the immigration office for 1900baht rather than slog all the way to Lao to get a single entry tourist visa?
Still if that's what you want to do you could go to Lao when ever you want, as long as you stamp out of the country on or before the 7th of April you're fine.