I actually found the second link you posted after I posed the question in this post. I like that combination and intend to try a few. I always preferred the 375 gr., which is no longer offered, so I'll take what I can get.
I discovered that the sabots are made under contract by MMP, which is probably the premier sabot maker, and in fact may be the only one. Unfortunately Knight owns the tooling and won't allow the sabots to be released for sale. I had hoped to have the ability to experiment with other bullets, but for now I'm stuck with what Knight offers.
Meanwhile I have found a couple suppliers of lead conicals and I'm going to try them also. The suggestion of using 32 ga. wads does intrigue me, and I think I may give that a go as well. I'll post a report of all the results when I have collected the data.