I contacted
Spannerman about a new c&s set (tsubaki sigma + steel JT), got it fitted in Shirlaws at the major service. Then fitted a Scottoiler and 11k later chain is still good (the old DID managed 18k but was completely f**&ed by then).
Give it a good clean and lube, and you'll see. If you need to adjust it every week, then it's time for a new one.
For c&s you can also use B&C express.