Sight Recomendations?

[Glockinstine]

Hello, I have had my XS Express (dot the i) on for about 5 trps to range and about 500 rds. I can get on target very fast but cannot do good groupings and think I might change. I was shooting nice and tight with the stock sights but don't have them anymore. Any recomendations?
Thanks

[Dingus]

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