What Kit said, there is no straight swap available that I am aware of but lots of options to replace with new from Hagon through to an expensive fully adjustable Ohlins.
We have quite a few threads about this that you might find helpful too.
Also a lower budget option is to have the stock Showa unit re-built. I had this done on my 2004 Sprint ST to very good effect and it was a small cost.
Some lesser equipped suspension outfits will say "ït is not rebuild-able".
Well it was not designed to be rebuild able but rt can be done effectively and economically by someone with the know how and the right equipment.
This is a pretty good thread to help answer your questions. Aside from the Sprint GT shock being a swap for the ST, nothing else OEM will fit. Many people here have had great success having their original shock rebuilt with updated valving and an appropriate spring for their weight & riding style.
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