Keep in mind you as a Canuck can go to the Canadian Embassy here, fill out the affidavit of income from abroad stating you get at least 65K baht a month and use that for proof of funds to get the Non-O from a thai consulate nearby OR to get it from the immigration office in Chiang Mai for 2000baht without the need to bank any funds at all
Although seeing as you're on an STV/covid extensions you would need to bounce out and back to get OFF those and on to a new 30 day visa exempt entry stamp. and that might be the best way for you to go about it as it won't tie up any funds in a bank here.
Now as far as Vientiane, that thai consulate requires an online booking to use (no booking you don't get in the door) as they don't allow walk ups.
You will want to read the website and requirements for the visas carefully before you slog all the way up there
Here is the link to make a booking for an appointment so you can turn in your visa application at the thai consulate in Vientiane
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I know YOU can get your 90 day single entry Non-O there based on being over 50 (with just proof of funds and proof of age)
BUT
I don't know whether they'd sell your foreign spouse a 90 day single entry Non-O based on "trailing spouse of a retiree" because you don't have a year extension yet 🙁
AND
I don't know if burmese are on the list there saying their visas take longer to process. 😕
There is NO insurance requirement to get that Non-O visa or to get the year extension after you get back to thailand and run the 90 day entry stamp down.
Both Savannakhet and Vientiane have near carbon copies of the requirements for a Non-O based on being over 50 (retirement)