Tons of wheels "fit" man... Stock STi BBS's fit the SVX just fine. If you want a nice stock alternative (16x8"), RX-7 "FD" wheels are a great option...
When I sold my SVX a few years ago, we took one of my 18x9.5" Axis Reverbs off the STi and bolted it to the rear of the SVX, then lowered it down. It wouldn't go down all the way (those wheels had a 25mm offset), but it DID show us that with the proper offset wheel and a nice stiff suspension, we could probably get 9" - 9.5" wheels on the car no worries...
Use the Offset Calculator:
http://www.1010tires.com/wheeloffsetcalculator.asp
and Tire Size Calculator:
http://www.miata.net/garage/tirecalc.html
combined with measurements you take to work out the best size wheel... Obviously rolling your fenders will help get a little bigger wheel in there as well. I see you are up there in IL. There MUST be some good Suby shops up there. See if you can enlist the help of one of them... Anyone can tell you stuff on the internet, it's your choice to believe them or not. But good, real world HELP is hard to come by - and almost ALWAYS cost something. With the SVX, always be prepared to pay if you want to start customizing things
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2020 Subaru Outback Touring - Wife's first Subaru
2005 Volvo V70R - 5-cylinder love! :Heart:
** SOLD **1998 Subaru Legacy 2.5GT Wagon - MOST RELIABLE car I've ever owned
** SOLD **2006Subaru WRXSTi (Former "
Boxer4Racing.com /
Continential Tire" STi) - Built EJ22t block / EJ207 JDM STi "big port heads" - 9,000rpm MONEY PIT!!!
** SOLD ** 
1995 "Tree-Hugger Green" SVX L AWD(5 MT) --- "Gumby" 130K miles
#399 in MY95, my original love...