Peske 8900e?

[David kerr]

I finally got around to replacing the rear shock with an Ohlins that i had under 
the bench and to my suprise i found a non-resevoir penske. There doesn't seem to 
be a model number on it but according to the Penske website it looks like an 
8900e series. Picture attached. Web site here:
http://www.penskeshocks.com/Motorcycle-8900E_Series.php

They list for about $600. 
Is there any way to confirm it's not an older model?
What's a fair price? $300 obo???
Anyone here interested or know someone who might be?

Thanks,
David