BAG Day Gun Goodness

So, before this moon-battery with the 2 McCarthy started, I was considering converting my decent BAG Day gun into an Honest-To-God battlerifle. This would entail replacing the stock and getting some decent detachable hi-caps.

Figured $150 for the stock and 2 mags. I could buy another rifle just like it for that much, but this'll give what I've got some utility. I start poking around the internet, and what do I find?

In order to stay a few steps ahead of breaking importation laws, I have to replace some of the internals with US made parts. See, AFAIK, it works like this:

@I've got a Curio & Relic gun. As such, I can ignore that parts-count game.
@I replace the stock with something more useful, I've just assembled a non-sporting, foreign assault rifle and voided C&R status. This is a Bad Thing, they'd have us believe.
@In order to avoid doing this Bad Thing, I must replace some of the foreign-made internals with identical US-made pieces.
@I will then have a US-made sporting rifle.

This is a *edited* joke. I've got to budget an extra $40 (on a college budget, getting 8 hours a week) to buy US parts that look and work identically to the foreign parts already in my rifle. Whoever came up with this should be tossed in jail, for life.

With a sign that says "Cop" or "Snitch" around their neck.