I just did a quick search and came up with a couple places to check for forend screw swivel studs:

http://www.grovtec.com/products_rifles.php - look almost at the end of the page. Click the Dealers tab at the top for a dealer near you.

http://www.gun-parts.com/accessories/ - about halfway down the page on the left.

If they don't have them I'll try to make a batch in a couple months.