scope or sight

[frumpy]

Just bought my first firearm today, a Mossberg 500 combo with 3 barrels. One of the barrels is the rifled slug barrel and I need to get something for it so I can actually aim. I'm not sure what route to go and looking for some input, either way not looking to spend a ton of cash.

 

[sunray]

Hi. The slug barrel should have an integral scope base. Think low magnification scope and rings. A red dot sight would be an option too.