Don't do it. Lasik modifies the outer part of the lens so that you can see
better in the daytime. Unfortunately, this ends up destroying night vision
when the edges are unmasked by the iris.
Better to keep what you have and refocus the eyepiece to match your eyes.
Astigmatism can be corrected by the addition of a cylinder lens that you can
put on the end of the eyepiece - just get a lens from your optician with
only the cylinder part of your prescription and you can make a cover to go
over your eyepieces that will fix that problem. Also note that you need to
mark the cover so you know which way the cylinder goes.

--
Bob May
Losing weight is easy! If you ever want to lose weight, eat and drink less.
Works evevery time it is tried!