I have identified the main lock as your part #82-002, Sliding Door Handle Set, 6-5/8"
However, this part does not come with the other part, installed in the accompanying door, which grabs the pin (or teeth) coming from part 82-002 and locks both doors together.
The doors were installed in 1992.
The measurements of the old part are 3/4" wide by 2 3/4" long.
A home owner from San Antonio, TX says:
October 28, 2016
I think the part # for this receiving part, mentioned before, is #89-003. If this is the case, please confirm. However, it does not come with screws. Do you sell the screws separately.
Tom from SWISCO responded:
November 1, 2016
Thanks for posting. The part you need is known as a keeper. The 82-002 handle set does come with one, actually. You can see it in its product photos.