Does anyone know if someone other than Anarchy makes hollow bolt extensions for use with the silent capture type recoil springs for AR's ? a few years back I found a polymer one somewhere online for around $30 if I remember right, and now the only one I can find is made by Anarchy , and they run around $65 , I've picked up another Gen 3 Law folder and want to use it on one of my AR's that I'm using a Armaspec SRS on .