ABS – don’t know
Steering angle sensor – I think this a fairly pricey part
Top engine mount – Lemforder OEM from eurocarparts (I’ve done mine IIRC £50)
Lower wishbones – genuine Volvo only (don’t skimp on these) £100 per side plus non reusable bolts from Volvo.
Track rod ends – Lemforder (Volvo OEM) from Eurocarparts ~£30 each
Exhaust probably needs the hanger replacing as mentioned previously (unless it tore a hole like mine did)
The mechanical items listed are consumables – the electrical stuff isn’t but also isn’t unheard of for these P2 Volvos.
Personally I’d stick with it if you haven’t had any fuelling/injector issues and the car is rust free underneath – especially around the inside of the front suspension turrets