Hi Pete, yep, you're quite correct re the pricing of many of the H&N pellets, including the popular (and excellent) FTT.
Now, as regards those barrels, that .22 Mercury S of mine loves the amazingly well-priced Excite Hammer. So maybe worth giving them a go in some of yours?
Plus, am I remembering correctly that H&N bought the rights to the Defiants, or was I getting that mixed up? You never know, if the new relationship flourishes, BSA might be able to make some "custom demands"?