Check with RT specialties, he seems to carry things like that. If he doesn't you can get "pushlock" (those round washer looking things that have what looks like a star pattern in the middle, they get pushed over studs). Also, I believe those nuts are self cutting stamped sheet metal nuts which are available I think even on Amazon as the were used one many things, you just need to know what size you need. I have seem them also sold as "speed nuts" I think.