If you're set on a Smith for this, and you don't want to dump the loot for a serviceable 16 or Pre-16, you may have nailed your best option. The only alternative I can think of right off the top is to take a K-38 with a shot-out bore , then sleeve both the bore and the chambers to make it a .32.

Are there any non-Smith alternatives you would consider? Isn't there an old Colt .32 Target revolver that was pretty good but would be cheaper than either a 16 or a modified 14?

If you get a 16-4, nothing says you have to shoot H&R magnum rounds in it. Does the accuracy deteriorate if you shoot .32 longs in the chambers that would accommodate longer cases?

Good luck. Nice project to contemplate, but I think it might get expensive to implement.

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David Wilson