I'm certainly up for a DIY job. I've already cleaned out the base of the slot and I'm happy to file/sand down the bottom of the nut, in fact I'll likely fit a new bridge nut as the previous one is a bit chewed and chipped in places. I think at £15 ish I'll try that first... just got to make sure the slot is correct size for the UST.
Message sent. I did find a replacement which I believe is called a 29R type but it was £110... almost 50% of the value of the guitar and I could likely buy a complete new system for that much!