I've had a few of the Bower wildcats, but the one I've kept for 10 years with no plan to ever sell is my 6.5SB. Bought it because it easily had the best long range precision potential of all the proprietaries offered by Don. Kept it because it does that in spades. My 15" barrel is a bit of an oddity in that instead of being a re-chambered factory barrel as most of the Bowers were, it was made from a premium blank by Bullberry, then sent to Don for his machinist to cut the chamber and make dies for it.
You won't have a problem for only 200 yards, but IMO the biggest long range limiting factor with any handcannon is the available optics for them. Many of them are capable of extreme long range accuracy, but the pistol scopes are just not made to equal their potential. When I shot my 6.5SB in the 1000 yard fun matches for a couple of years, I block mounted a 36X rifle scope on it, shot prone from a Bower rest and once locked on target moved my eye away from the scope for the shot.
I don't think redlining with the 6.5SB is a problem myself. Safe reloading practices working up loads makes safe loads for your particular habitat. I have no doubt Don reached higher velocities (and pressures) in the lofty environs of the CO Rockies than I ever could here in the low, hot & cold desert southwest. But then there was no need to push the envelope IMO. I found very accurate loads well below Don's published maximums.
I think Kyode is probably right. While OTT can duplicate it no problem, I don't think they could call it by the same name. Kind of like TC now offering the 375/444 (SSK 375JDJ). Maybe they could call it something like 6.5/307, 6.5/356 or 6.5/444 Short.
As SWH suggested, there is a box full of factory and wildcat offerings that can easily handle whitetails to 200 yards. So no real need for the 6.5SB just for that unless you also might want to shoot or hunt with it at MUCH longer ranges than 200 yards. BTW, I had a SSK 6.5JDJ too, and it would have handled whitetails nicely at 200 I think as also said (although I preferred my 257JDJ's over it).
One thing for sure, you can go to the range and will probably never run into anyone else with a 6.5SB. I've met and made some great friends at our large GC when they came over to see what the heck kind of pistol I was shooting at the 500 yard berm or 800 yard gong (usually either the 6.5SB or one of my 375JDJ's).