There is a Zetoc SRU server. This has been implemented with the Index Data YAZ Proxy which provides for both SRU via HTTP GET and SRU via HTTP SOAP.
The Zetoc SRU interface is accessible at:
http://zetoc.jisc.ac.uk:210/zetoc
If you try it please let us know how you get on with it.
Searching uses Dublin Core Metadata Terms and CQL
As an example, the following SRU URL does a search for "railway"
and requests 1 record:
http://zetoc.jisc.ac.uk:210/zetoc?operation=searchRetrieve&version=1.1&query=dc.title%3d%22railway%22&maximumRecords=1&recordSchema=mods
To know how to format the query look at the CQL documentation on the SRU website.
The default Zetoc record format is the MODS XML format. Other record formats are available through the Web, Z39.50, and OpenURL interfaces.