Living in Germany I know this problem very well.
There are not many headphones in the price range of sr225/325i that have a very close to Grado sound.
In my limited experience the closest sound to Grado I found was in two vintage AKGs - K240 Sextett and K241. The sextett has the flavour (and a little more bass), and the K241 has the speed but an airier soundstage, but both need decent amping.
Also vintage SFI orthodynamic drivers can be tuned to have a similar level of crunch and sparkle, and similar speed/attack, but they don't have the same overall flavour and also require a capable amplifier.
I found there were only incremental differences between most of the SR line of Grados apart from the 325i which seems to have a far more piercing treble presentation.
Have you considered simply getting an SR80i? That's probably the closest sounding to the SR225i (and RS2i) but has a tiny bit less detail, air and bass control.
It's probably the best value for money Grado there is.