One of the things that fascinate me the most with your build is: How did you go about determining the relationship between the pivot pin on the front of the breech piece, the mortise in the breech piece, the "C" hook on the forward barrel lug and the rear barrel lug ? Not to mention the lever and links !
The 1st Model Maynard had a set of screws and an adjusting piece to adjust the head space or as they called it "barrel gap," before they simplified the breech piece and did away with all those extra components after the fire in 1861.
As far as I know no one manufactures the tape primer (other than roll caps for cap pistols and I doubt they would work). Those original compositions were not only extremely toxic and corrosive but quite dangerous as well.
During tape primer manufacture at the Arsenal in Bridesburg, PA they had an entire sheet in one of the presses explode. They said the report sounded like a 6-pounder going off. At Massachusetts Arms Company women used to shellac the tapes to make them water proof, roll them and put them in the little tin canisters. Ten rolls to a tin. Women also checkered the pistol grips of the Adams revolvers they manufactured.
Several years ago some enterprising individual made the "Tap-a-Cap" where he cut the caps from the roll caps and would place up to three of them in a cup and thereby make his own percussion caps. Not sure how successful that was. Only important thing is to get enough flame to ignite the black powder - with some sort of consistency.
Yeah - Both Maynard G. Krebs and Maynard rifles were popular in their day and I still get a kick out of both of them.
MaynardG