Which front Tires to go with Dunlop Direzza Sport Z1 Rears

[Klepper1]

I am putting together a set of track wheels for my wife's 135is.

I picked up a set of OEM 264's a week or so ago, and I just recently found a great deal on a set of 255/35/18 Dunlop Direzza Sport Z1 tires for the rear (9.5/32nds and no repairs/patches).

I am having a hard time finding a matching set of Z1 225/40/18's for the fronts. If I can't find any fronts before the next track day, can I use a different tire for the front axle? Maybe Z2's for the front, or Hankook R-S3 or R-S2? She is in the novice run group at the track, but her next outing will be the third time on the track.

Thanks

[Klepper1]

nobody?

[BrokenVert]

Dunlop Direzza Sport Z1 Fronts - never mix and match tires