Lip lift caused thin nostril sill. What are my options if it doesn't even out?

I can see what you are referring to but you didn't provide a time frame for your surgery.  If the right nostril is too narrow there really is not a great deal of simple procedure you can do to remedy this situation.  If there is noticeable asymmetry then you are likely going to need the opposite side narrowed.  From the photo that you have provided, some narrowing would not look bad on the wider side.  Please wait a few months prior to entertaining any further intervention.

I see a slight difference. If it doesn't resolve in a year. it would be easier to reduce the bigger sde to mach the thinner side.

Postoperatively, after a lip lift, you can anticipate bruising and swelling that will be noticeable to you and others for about 1 week. After the sutures are removed or dissolve, depending on the type used, there will be redness along the incision line for 4-6 weeks but this can be covered with makeup after about 10 days. Sometimes the upper lip lift is overcorrected with the initial procedure and will slowly assume its final position over weeks to months.
Without knowing how far out from surgery you are, seeing more postop photos, and evaluating the preop photos it is difficult to provide any further advice. 
In general, recreating a natural looking nasal sill is nearly impossible. But you may end up healing just fine.