So after 20 minutes on the innanet it seems there's a boo-koodle or so of mfgs who make side charging bolt carriers that fit the BCA receiver. And it appears bolts fit them. So 'spose I'll run some cotton into the chamber and maybe down the barrel to see if there's any grabby spots and maybe do some arm exercise with JB paste. Similar for the BCG and bolt just to check finishing. After that guess it's pow-pow time to see if anything blows. Have a young friend that did some shop work whenever he could while in the Navy and know he has put together a long and a short for him and his wife. We may owe them dinner. Any more input appreciated. And to the OP sorry for the jack, hope it was useful to someone else.

“When Tyranny becomes Law, Rebellion becomes Duty”

Colossians 3:17 (New King James Version)
"And whatever you do in word or deed, do all in the name of the Lord Jesus, giving thanks to God the Father through Him."