pabs

I have been trying to find an answer to this problem for ages...The situation is this:
I have a '95 wrx sti, I would like a little more bhp, perhaps better fuel economy and not to have to worry about putting in 97RON and Octane booster. I know you guys with newer scoobs can achieve the above with tek3 remaps....but what can you do if you have an earlier model like mine?

As I can see it there are several options which may achieve some of the above:
Apexi SAFC (advances timing so not ideal), ScoobyECU (not easy to find), Gizzmo chip (Nobody seems to know about these).

Can I have opinions please on how I can best achieve the above without having to spend the earth.

Cheers