The stock ones aren't known to fail under normal or even hard use.

There is an STI optional timing belt that is the factory part the rally cars used but it's $$$$.

Subaru is pretty sure of their timing belts durability if they reason a 100,000 km change interval is the norm.

Budget to change the Idler bearings, tensioner bearing, waterpump (t/belt driven) and the cam seals whilst your in there with the front half stripped.

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[CENTER][SIGPIC][/SIGPIC][/CENTER]
[CENTER][COLOR=#ff0000]Built Ej207: Semi-closed RA Cases - Wiseco Forgies - Manley rods - BC 272 cams - GDA Heads - billet f/whl - Vi-pec - WbO2 - 800cc Yellow tops - TD05-20G - 409Hp ath @ 1.75bar on E85[/COLOR][/CENTER]