A little progress. First, John Smith is correct - the designator TS
10.220/xx is indeed an LBA thing, and it appears to still be in use.
Here's a list of the categories:
http://www2.lba.de/dokumente/zuger/r...tand%20neu.pdf

Category 4 is for Sailplanes, which is he http://www2.lba.de/dokumente/zuger/04-segel.pdf
Note the September 2010 issue date. Note also the form of the number
in the first column, this really is a TCDS number.

Category 12 is for Flight and Navigation Instruments, which is he
http://www2.lba.de/dokumente/zuger/12-1-navgeraete.pdf
Note the form of the number in the first column, it appears to me to
not be a TCDS but rather a TS number. Technical Specification, maybe?
Unfortunately, the 10.220/48 designator for the Winter altimeter in
question isn't in this list - don't know why.

I picked another number, 10.220/40, for a United altimeter which I
know is in production, but I had no luck in finding the text for this
TS document on the Web. So at this time its still unclear if the a LBA
TS will link back to a TSO.

-John