Can't help you with mounting your large light; short of making a mount out of angle-iron and U-bolt muffler clamps, I don't think you're gonna find a reasonable way get it attached to your rifle.
I will suggest this as another option; I recently bought one, and I was so impressed that I just ordered another:
600 lumens, although the chart provided with it seems to indicate it drops back into the 500+ range a bit after the first few minutes. Even at 400-500, in this size light, there's not much else out there that will match it.
Not sure how it (or your TK-41) would hold up under recoil forces, though.