You can test dillution on yourself, its not that bad, I've done it several times. Buy an at home test kit from your local pharmacy, thc only. Read up on the dillution sticky and go for it. If you chose to use dillution, the day of the ua use gatorade instead of water and skip the aspirin its now outdated. Also try to load up on red meats to raise your creatinine levels but you need to start 1 -2 days before your test.

Synthetic urine for subbing is an option. Search for this topic, I do not know enough to feel comfortable giving advice on it.