I used my thumb to hold it shut this last weekend shooting mine suppressed for the first time. Benjio in the suppressor forum suggested this.
"One thing I did for my 10/22 that keeps the action shut is a small piece of hardwood (oak or something like that, whatever you can get, even plastic cutting board material will work good). Mill it down to fit in the space just aft of the bolt handle so it "slips" into the space where it touches the side of the bolt and sits between the upper and lower surfaces of the receiver if that makes sense. Then you go to a store like Rockler and get a rare earth magnet, a small little one. Mill out a hole just big enough that you can put some gorilla glue or whatever in there and then press in the magnet.
If you put it together right, you'll have a little block with a magnet that will hold itself to the bolt and keep the bolt shut, making it sound like a bolt action; MUCH quieter. You just gotta pull it off and manually cycle the action to reload. I'd take a picture of mine for you but I lost it and haven't built a replacement... "
You can also buy a bolt lock for the 10/22.
http://www.silencerresearch.com/jg_bolt_lock.htm
Mine, since threads are worthless without pics.
ETA: Just realized my post doesn't help in any way, shape or form...my bad.
I am also interested in the product the OP is searching for.