I'm sure some others will chime in to help but I have a suggestion.
Look at this post about lasers and see what you think and as far as night sights rather than getting a cheap model save up and get something that will not let you down like trijicon.
Note the second to last paragraph.
http://www.officer.com/article/10643657/the-skinny-on-lasers
Trijicon
https://www.trijicon.com/na_en/products/product1.php?id=HDNS
If that breaks the bank for you something like this is acceptable for a reasonably priced night sight.
link
http://www.amazon.com/Meprolight-Springfield-Tru-Dot-Night-barrels/dp/B0002IND18
Look at this post about lasers and see what you think and as far as night sights rather than getting a cheap model save up and get something that will not let you down like trijicon.
Note the second to last paragraph.
http://www.officer.com/article/10643657/the-skinny-on-lasers
Trijicon
https://www.trijicon.com/na_en/products/product1.php?id=HDNS
If that breaks the bank for you something like this is acceptable for a reasonably priced night sight.
link
http://www.amazon.com/Meprolight-Springfield-Tru-Dot-Night-barrels/dp/B0002IND18