Can't find the specific answer... I know many e46x wheels can fit the f30x, but what ET should I be looking for???

I'm in immediate need of new tires on my e46, but I got to wait until my kid gets out of daycare in Sept to get a new car. I'm getting some form of f30, but not sure what.

I need wheels and tires I can throw on my e46 (like 19x8.5) that I can get away with for 6 months until I get an f30. If I did 19x8.5 with a 35-38et for the e46, can I toss them on an f3O down the road?

Even if the 19s look a little large on the e46, I'm willing to make do. I just don't want to buy wheels and tires twice this year and I have my heart set on an f30 next fall.

Thanks for your time.