The County Ckerk offices in Oregon are closed right now due to COVID-19, but you can still get a valid Oregon marriage license.
In Oregon, you can get your license in any county, you do not have to live in, or be married in that county – you just need to be married in the state of Oregon.
No in person services are available but Washington County offers certificates by mail.
Instructions for licensing by mail here.
Allow 3 days to receive the paperwork after you mail in your request with a self addressed stamped return envelope. Also remember most neighborhood grocery stores have stamps you can ask to buy a book of stamps as you check out, you do not need to go to a post office.