I currently have .22LR, .357 mag, and .44 mag with iron sights, and a 10" .30 Herrett with a 4x scope on it. Just looking at the capabilities of the .30 and .357 Herretts, I would be tempted to scope it. However, as you said, the scope will throw the balance off and affect the handling capabilities. If your expected shots are limited to 50yds or so, I would just stick with the irons personally, as I feel comfortable shooting to about 60yds without a rest (although a rest is always preferred) or about 85yds with a scope in a hunting situation. I am working on increasing my range with both sight systems, and have shot some with the .30 Herrett out to 200yds on the range with promising results. I want to say the front sights on the 10" .22LR and .30 Herrett are brazed on, as I don't see any screws holding them in place, so I think your fears may be well founded as afr as not having enough metal to drill and tap into, but I am no gunsmith. Not I have seen sights mounted by the drill and tap method, and also dovetailed in on barrels thinner than these, so I still think it may be very possible if you decide to get sights mounted after all. Best of luck.