Red Dot Magnifier?

[PO2Weatherly]

Ok so I have this Truglo red dot sight:
Amazon.com: Truglo Red-Dot 42Mmx2 Sight, APG: Sports & Outdoors

I would like to get a magnifier with slide to side mount so I can atleast shoot at the 100 yard range, it is my first red dot on my first AR so I was not looking to spend to much on a red dot it has worked great, I have gone to the range 3 times with it and was blowing holes(very tight groupings) in the paper at 25 yards with .223 and .22lr, it is a x2 but only rated for up to 30 yards I want to keep it for a while till I can afford to upgrade to something nicer so any advice on a decent magnifier I have been eyeing a sightmark tactical 3x magnifier, since my red dot is already 2x would getting a 3x magnifier make it good to shoot at 100 yards? Let me get your feedback and any suggestions.

[willow]

Primary Arms from what I have read has good magnifiers. I would probably email or call them to make sure it will line up correctly though.