Searching for C1380 mortise sliding door handle parts

Hello,

The part in your photo may be a type of thumb lever but we would need to see the rest of the assembly where it installs to get a better idea of what you need and research your replacement options. Thank you!

Thank you for the additional photos. We can't replace this assembly or its individual parts with exact replacements but our 82-030 can replace this handle set with the top-mounted thumb lever with an offset locking bar without adaptation.

What's confusing is that the original handle doesn't look like it has a centered latch since the thumb lever itself is, for whatever reason, mounted above both screw holes. The reality is that when that thumb lever is turned, an internal arm mechanism reaches down the spindle and turns it. 

Our 82-030 works the same way but its thumb lever is centered already. It doesn't need that additional (and redundant) arm mechanism.

Thanks for getting back to us with this additional information. It seems like your style and dimensions are closer to our 82-080 handle set. Unfortunately, this won't work for you since the type of thumb latch spindle that your handle set uses differs from ours. 

For that reason, the 82-030 would still be our best replacement option but you would need to drill new installation holes in your door to accommodate the 3-15/16" hole spacing. I'm sorry that we can't supply a direct replacement at this time but