The other day I saw an "open box" 300 f/2.8 IS offered for sale by Henry's Outlet Centre in downtown Toronto for $4.6K CAN. The lens sure looked new and dust free to me.
If you have some connections with the shop and/or you are their established customer, you might even be able to get some sorta deal there.
Unfortunately I understand the Outlet Centre doesn't give refunds unless the stuff is clearly defective upon delivery. If you change your mind about the lens within a two week period, they would give you a store credit. At least that's the way I understand it. If interested, you better ask them for all the details.
(A note to those that are not within an easy driving distance to Toronto: please don't ask me to check the lens for ya unless you are prepared to compensate me for the time I'd have to spend doing it. )
Lastly, a disclaimer: I have no business associations with Henry's, nor would I benefit from the sale of the subject lens in any way.
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