There are many different choices when it comes to air filters.  K&N makes drop in replacements for the 3/S and they also make a FIPK.  The drop in replacement will cost you ~$40 and the FIPK will cost you ~$150.  The cheaper alternative to the FIPK is the Aircharger unit that is made for the 95-99 (#63-1000) Eclipse turbo.  It is half the price of the FIPK and is the exact same thing.  The reason it is cheaper is because it is not approved for use in California.

Another option is the HKS Super Mega Flow and the Power Mega Flow (for VPC).  These units are around $230-$250.  Other units made for the 95-99 Eclipse turbo may fit also, since the MAS of the two cars is shaped the same.

The N-speed type R air filter and Weapon R air filter are new units that I'm not familiar with.

HKS Super Mega Flow

HKS Super Power Flow (for VPC)

K&N FIPK