900sie Front sprocket

Hi,
Thought I'd change my chain & sprockets now my bikes parked up for winter.
Ordered a new chain & rear sprocket but cannot find a front! I've read on here that the 900sie model has its own style with a shoulder on each side.
The company I've ordered the chain & rear sprocket from are saying there all the same.
I've got the part number but cannot find one. Emailed moto Rapido but not heard back.
Does anybody know we're else to source one.
Thanks
Nik