i have a 1998 imreza and want to go back to standard soil springs, ive been offered standard springs from a 2001 model, will they fi the standard struts?

I believe 2001 onwards are different to the classic due to the size and weight difference in the cars. however I may be wrong.

Good question not sure myself to be truthful I know they made a few Tweaks to the suspension stiffer springs, larger anti-roll bars and so on 

Good point - they may fit but due to the differences in the cars they were made for you could end up with a ride that is still too stiff for you