The oil pump is located behind the clutch. Remove the reverse threaded nut with an impact gun. Pull the clutch/sprocket off of it's shaft then remove the dust plate. The oil pump should now be visible.
Talon was imported into the U.S. by MTD and sold under the McCulloch name. Since you did not provide your model number you'll have to match your saw up against an identical MTD/McCulloch and then locate the parts breakdown. Talon is also sold by Husqvarna under the Talon name overseas and a parts breakdown should be available by contacting Husqvarna.
Husqvarna customer support is fantastic. I sent them an email requesting the parts breakdown. They responded with the parts breakdown later the same day.
Example: My Talon AC310518 is actually an MTD/McCulloch MS1842AV. Oil pump kit (shaft and bushing) is Husqvarna part number 522189801 or MTD part number MC-9059-310504 pump bushing and MC-9073-310502 pump shaft.
I realize this is an old question, but since I recently encountered the same problem, this solution will hopefully help out other Talon chainsaw owners.
sherwood
March 2013
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