To ronach,
It seems to me that you are barking up the wrong trees. Step one is the always the printer manufacturers web site or a email to the former and microsoft. There well may now be a emulation driver for vista that will work with win 7.
But even then, if the printer manufacturer is going to write a win 7 driver, they generally wait until after the OS is officially released.
And because other drivers for more modern devices are probably keeping them more than busy, holding your breath may not be advisable.
I for one see no reason to assume the printer will remain driverless or that it is time to say its obsolete. Its also possible some DOS emulation driver may be written for win 7 if it does not exist already. Does win7, like win xp, have a compatible mode for legacy programs?