Thank you for your question. It is certainly possible to surgically modify your current supratarsal fold lower on the eyelid to try to achieve a mono Asian lid.
However complete symmetry is going to be very difficult if at all possible because the mono lid on your right side most likely has a...
The problem you are describing can be improved but only at expense of worsening droopy eyelid. There can be a happy medium where there is some droopiness but the can blink and close the eye. See an oculoplastic surgeon.
Not having seen you would be tough to give an estimate but I would say in the area of 3-5000 would cover most of your costs.also do you want to be sedated or do itm under local?There are a lot of things to consider.Hope this helps.