On a brand by brand basis, we offer a special order option that allows you to order products from a brand that REI does not normally carry. This option can only be completed from your local REI store, and is dependent on the vendor and the stock they have on hand. While we do have a special order relationship with Altra, it also looks like it includes only the older model of Olympus (3.5). You'll need to have the customer service specialist check on availability and options with Altra before placing your order.
Hopefully this helps, thanks!
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