So this is what I did...
First I googled for 3CR17562-9 and found out that its most likely this model:
HP E4500-48 Switch (JE046A) 3Com Switch 4500 50-Port 3CR17562-91
Then I went to http://www.procurve.com clicked on "support" in the main menu (at top) and then "support lookup", ended up here:
http://pro-networking-h17007.external.hp.com/us/en/support/converter/index.aspx
At the above site I searched for "JE046A" which gave me information that the E4500 is end-of-sale since may 2012 but this doesnt matter since you want to locate latest available firmware to download.
In the search result above there is a link regarding "software download" which I clicked on and ended up here:
https://h10145.www1.hp.com/downloads/SoftwareReleases.aspx?ProductNumber=JE046A
And voila!
E4500_03.03.02p21 looks to be the latest available version and was made available in january 2013.
Here is a directlink for the above download:
https://h10145.www1.hp.com/downloads/DownloadSoftware.aspx?SoftwareReleaseUId=10022&ProductNumber=JE046A&lang=&cc=&prodSeriesId=&OrderNumber=&PurchaseDate=