Normally when setting up a relay that fast you use a push-pull or
polarised relay. The first has two coils and the second has a magnet in
the armature and will be operated by reversing the polarity of the current
in the coil.

One way to speed up your relay is to use a push-pull driver and drive the
'upper' side (the one that replaces your diode) with a very short pulse.
This will kill the field or part of it and leave the rest to make a safe
voltage pulse (that is lower than your Vceo).

Another is to use a drive transistor with very high Vceo and no diode. If
the manufacturer is not lying it should work. I've used BF457 like this
once but not for speed reasons (I needed the high voltage pulse). BF457 is
rated to 250V I think. You can use any of the many final video amplifier
NPNs that are mass manufactured for the color TV and monitor market.

Imho for a mass market application this is something that you will regret.

Peter

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