I thought I had one kicking around. After digging through my Sheafer parts I found bag of pencil mechanisms for Lord only knows what model Sheaffer pencil, but not for a Prelude. I'll buy, but I'll also trade a BP mechanism for your pencil parts. Contact me BC, or by email. I'll see that sooner - I miss a lot of PM notifications at the top of the page here. Address is on the website.