Another 727 converter Q

I am about to swap in my new engine into my D150.
/6 going back in, in front of the original 727 which is still working great.
No I ain't dropping down to a 904
Yeah I know the difference between a 904 and a 727.
I've been All over with people about those 2 subjects before.
Question/problem being is that my particular 727 is a lockup version.
I am probably gonna be looking to slide a new converter in when the engine comes out. Mostly because I'm pretty sure I have a bad tooth or 3 on the ring gear. I'll know for sure once I get the original engine out from in front of it.
Converters are all over the place for 727s unless like me, you're stuck with the lock up version.
The lock up has never worked for me, but according to the PK number it has it.
And the input on a non Lock up is different, so I can't stick just any converter into this trans.
What is available for these, besides stone stock rebuilds? I'm not looking to go any deeper into the trans right now besides the converter and a front pump seal. It works too good otherwise, to open it up.
I did a fluid and filter swap when I got it running, only 100 miles ago. Before I knew the Lock up was DOA. But I really don't care about that either way. Only reason I dropped the pan then, was the pan gasket was leaking all over the place. And the old fluid looked as clean as the new fluid that I put in.
So what's available for a converter for a lock up 727?
How much different is the factory hi stall vs the factory lo stall version? The trans, as well as the truck ,are '85.