I have done something pretty evil in the past for leaky rims.... Silicone along the beads (With the tire off fill the beads and remount)..... Took my brothers cars unusable stock rims from 20psi a week loss on 3 of 4 rims to zero.... Yes it makes a mess of the rim and yes tire shops wont redo it for you if they take the tires off but his car is worth 300$ tops and the rims were going in the recycle bin anyways. 2 years later and as far as I know he has only had to add air twice.