This has been an education all onto it's own. The magnet trick and sizing information is appreciated. While I know this wasn't the cause, it made me think about the number of AR detents I launched across the shop when I built my first couple of them, also the spring I lost from a brand new Staggs 20/30-30 over-under back in the 70's. So I went searching and found a source for magnetic work mats. Don't know if they are the cheapest but they have several strengths and sizes. $43 will get a 19"x24" that should help keep stray bits from disappearing (spring launched not included). COWRC.com is the site. I suspect it might be worth it not to have to go through sourcing a hard to find part. Glad to see you get a replacement.
Thaine
