I have a now discontinued Lyman # 379670, 335gr. mould, same profile as their current 378674. I only cast a few bullets from it as they turned out to be too heavy for the slow twist of my Rolling Block, so it's as new, and drops bullets at .379"/.380". $50.00 if you want it.
You might also try to find a Lee 379-250 RN/FP 250gr. mould. I have one of these which I use, and it also drops a .379"/.380" bullet, but with a bevel-base.
Regards, DaveF.