I decided to add the store bought R-134 to the system. The left vent was pumping cold air instantly and reading 15 at #7. I let the system completely empty the small 12 oz can while keeping an eye on the pressure. It never got past 16 at #7. It took about 15 minutes to empty the can. Both vents are blowing cold, hopefully it stays that way.

Thanks for the help!

Mike