Or you could try the monthly meeting/annual flea market on June 12 at the Pacific Northwest Tool Collectors in Hillsboro. Plenty of amazing tools and worth a visit in any case. Not sure you will get a type 11, though; that's getting a mite specific.
I suggest ebay is the quickest way to find one at the best price. See Whitney House Antiques https://www.ebay.com/str/whitneyhouseantiques
They are great folks and have a very good selection of cleaned and useable tools.
I am looking for one of these and can be reached at 360-409-3152. Thank you.
Stanley No. 71 Router Plane, type 11 complete, 2 irons minimum (1/4-1/2"), depth stop, and fence.