How much time do you have? I'm fairly certain that Oregon does indeed check for uric acid, aka urea. This is why you must ensure your synthetic contains uric acid.

Multiple brands do contain uric acid. However, the Quick fix I mentioned previously is what is most commonly used and I would feel very confident using it. Canadian Quick Fix 5.7-1

All that 'Canadian' means is that it contains Uric Acid. This is because Canada was the first place to begin testing for uric acid as a way to differentiate synthetics from human voids without using genetic testing, as a way to remain legal by their national regulations, as well as ours. (US federal - genetic testing in urinalysis' for pre-employment is not legal)

Depending on your timeline for your test, I would recommend just buying it online directly from the manufacturer. I'd link you, but it isn't allowed here. Some simple googling around should yield you the proper results.

As for subbing though, the key to success is to practice. And then practice a little more. Then practice again. Synthetics will pass the lab, it's the temperature check that people fail on. Research all you can, ask all the questions you can think of. I visit here regularly and will be very happy to lend a hand. But at the end of the day, research is your closest ally.

I'll keep checking in on your thread though man, let me know if you have any questions