Mehulkamdar,
A few months ago I did enquire with MartiniHagn about a special order for a H&W Kurz squarebridge action with large ring. The responce was that it is available only in small ring.
The Hagn lads probably have the best relationship with H&W. If they cant get one at their request, i dont know who can. However the Theo Jung site shows a large ring action that is definitely shorter than your regular 98.

The magbox is 2.8" on that H&W Kurz action. Ralf said it may be streched a little,(0.1") but 3.1 does not seem likely.

The only two new 98actions H&W make are Kurz and Magnum length. As you say, they are truelly magnificent actions, and after handling afew at Reno,I lost interest in just about everything else. I may just have to settle for something on the H&W magnum(300h&h) if I cannot find what i am looking for. Could also cut and weld a magnum to intermmediate length.