The relay is K1 in thefront dist /fuse box. Its the far rt hand side yellow one.
Its more of a start inhibit relay than a 'starter relay' as it gets its coil voltage from the auto-box selector to stop vehicle starting in D or R.
At that milage your starter solenoid/starter could be worn out too!
Check also, that (like what happened to me) that some animal in the past had fitted an immobiliser into the start supply from the Ign switch. I was unable to reset the immobiliser as I didnt have the 'key' for it. Horrible installation under my rear seat connected into all-sorts--Im slowly sorting through it!