That is exactly what I did, I bought a package of each kind of sabot, and once I found a tight fitting sabot that went down with just the right pressure, I settled on that.

http://www.midsouthshooterssupply.com/ and
http://www.mmpsabots.com/

have most everything, sabots are one of the cheapest improvement to accuracy you can get.

"Goldilocks tight". What is Goldilocks tight--not so loose you can push down easily, not so tight you have to pound it down, but "just right", tight, but goes down with a lot of pressure. That is Goldilocks tight, that is what you need in Smokeless Savages, and I believe also with Blackhorn. Also seat the bullet on the charge firmly, all they way down, with most your weight on the ram rod. Chap Gleason