See if you can get a AR15 type rifle. I have a Mini 14 and it is hard and expensive to find good after market high capitcy mags for it.
I love it, but you cant get goodies for it.
You can get ruger factory 20 round mags from the company on special for $29.00 each to commemorate the election.
www.ruger.com
you can also get mags from www.cdnninvestments.com