It's a tough call.
Perhaps cutting back one ravager, one razorwing, two venom squads, the leech pistol and a syrabite here and there would get you close to your goal.
EDIT - if you cut exactly these 4 units, the pistol and every syrabite, you'd be at your goal.
If there's less emphasis on vehicles in your area, you could consider having dissies on the remaining razorwing and possibly on one of the ravagers, saving you a little extra.
I think at 1250 points, relying on scourges, the kabalite blasters and a single ravager supplemented by grots is enough. This isn't the case if your enemy spams tonnes of tanks though.