Opinion:

If it were me, I would purchase either a hex or torx head stainless screws longer than you need and then cut them to length for each application. Make sure you have the right size and type driver or bit when you are at hunting camp or at the range in case you need to take the stock off.

I don't worry about the relative strength of stainless versus non-stainless steel. You are coming nowhere close to the torque values that would make that a factor.

When grinding or using a sanding belt on bolt ends, I shorten the bolt and then hold the bolt sideways and bevel the edge just a hair. The slight bevel takes the sharp edge off and eliminates the issue of threads rounding over.