You can accomplish the same thing with an assortment of compression springs.I ordered some button magnets from Banggood.com, they are 9/16" x 1/4" approximately, I placed one on each of the socket head screws that hold my 1" aluminum soft jaws onto the vise, it holds the steel parallels right where they are supposed to be!
Hopefully this is going to work without incident at least on aluminum, could be a problem with steel though.
Actually I ordered them twice, the first order, all I got was the empty package?? I think they are stuck to a conveyor in the postal system somewhere. They resent them double wrapped in foam this time and they came thru fine. There was no hassle getting them to replace the order, just a picture and an email.
Mine have a hole in the center of them, I would recommend that as it will aid in removal if needed.