Bottom metal inletting

[FLbuckfever]

I have a sr3 with feed lip that I want to put into a ag composites c.a.t. stock. What bottom metal should I use or at least what inletting I should get? I will not be running detachable mags if I can't find something that sits flush.

My options are :
Remington bdl
Badger m5
Hs precision dm
Hawkins bdl
Hawkins m5

Thanks for the help, this is my first build and quite the learning process so far.