Thanks for the info.

(By pretensioners I meant some kind of electronic triggering gadget which goes off in an accident, rather than the usual spring which just retracts the belt. Something which means the belts have to be specific to the Subaru rather than standard parts from Repco or wherever.)

I actually have a brand new seatbelt in the packaging, and while the longer tongue seems to suit the Forester the mechanism & fittings look just like the one on my WRX.

Basically trying to work out whether it's cheaper to get an off-the-shelf replacement or get these tensioned up.

Back in my HJ Kingswood days it was take it to bits and have at it with a screw driver, but not on a modern car in a modern litigious age.