It's hard to say, depends on actual flow..............a mag pump is rated w/ 2x the output supplied = it never comes close to rated flow. The Eheim hobby pumps are rated with the supplied output = they make all of their rated flow (which why you see many say Eheim under rate the pumps).
The 1260 will give you at least as much flow as you have now, likely a bit more.
Have you considered the compact line of pumps? The 2000 will give you 500+ at full throttle = likely real world similar to the mag 7. The 3000 is rated up to almost 800gph..........but.........they have switches on the outside to dial it down. The 3000 would give you the head room should you need it.