Can't go wrong with a SIG. How did you do at the gun show? Did you manage to sell them both? I had a guy come by my table that would have snatched up the AK in a heart beat.
It's a JAC gas gun. I'm not the expert here on gas, but Paco probably can answer that. I think they're out of production. Bart, didn't you want a BAR at one time?
Single action pistols like that are intended to be cocked and locked before holstering. Then you won't have to put your thumb over the slide when you do holster it. When you say the slide is loose is sounds like you mean it actually slides to easily. Remember it's only an airsoft gun and doesn't have a 20lb spring in it like a real steel gun would.
The easiest way would be to pin the receiver so the selector can't go to the full auto postion. Otherwise it's a bit more complicated to modify the gear box to convert it to semi only.
It has some merit, but there are down sides to it. I can change out my spring right now in about 2 minutes and at the same time relube my gear box without having to remove it from the gun. With this system, your back to a regular AEG box were you have to remove it and strip it down to do so. Also you need to spend a bit more to buy all the parts that are required to make the conversion. I'll just leave my SAW that way it is for now.
I believe Arizona Response sells them. They completely rebuild them using the correct amount of US made parts so they can be configured as Pre-Ban models. Down side is they go for around $1,200. Check them out at the next gun show Vell, the guns are beautiful. Otherwise, heck we're going to be in Prescott Saturday, we could stop by there on the way home if you want. I know they open at 9am but I'm not sure what time they close.