If anyone else stumbles across this topic, as I did when looking for a replacement trigger, you can still obtain a non OEM part (identical part no.) from several sellers on eBay. I have recently purchased one for the huge price of £3.86 incl. P+P and VAT! The seller is called shinyempire but they are part of a larger group called UXcell and the part was dispatched from within the UK and arrived within two days. Can't fault their sevice at all and now have a working drill once more.
Hope this post may be of help to someone else.
JohnyJackofall trades, May 2012