oliverstacy
I have a Win 94 BB in 375, but not in a singleshot. I am more limited in bullet selection than you. You might want to take a peek at my web site (the www button below my post) and see what I'm up to.
I'd look into some of the other bullet offerings in the 375 cal besides those made for the leverguns. You might also want to investigate Paco Kelly's writins about the 375 Win and what it is capable of, especially in a Contender action.
http://www.leverguns.com/articles/paco/375-356.htmAs for scopes, I'd suggest the 1X4 if it were me. The quick on-target time of the 1X would be really nice and 4X is plenty for the top range of 200-250 for this caliber.
A 4" high, 100yd zero is going to give you a max point-blank of about 250 with top loads and that is on an 8" bullseye. Most would stick to 200 or less.
I have no problems hitting a 8" steel plate at 300 with my 30-06 using a 4X scope. Other than that, go with the one that you like the most.
With top loads (250gr) the 375 will kick about like a 308 Win.
Enjoy it, I do mine. I may yet make a 375 barrel for my H&R. Will have to have a 30-30 barrel reamed.