I have a 25" '85 Raleigh Alyeska, which is one "step" below the Portage in the touring line. The differences? The Portage had 650b wheels (making this seemingly larger-than-25" bike clearly a 25"), and three pairs of water bottle bosses to the Alyeska's two.
I paid about $340 (or was it $325?) plus shipping for a super mint unridden 25" with original raleigh branded toe clip straps, branded black water bottle, orig everything. Freewheel was still gold colored -- no grease, etc. Catalog shot accurate and new. I consider that an excellent deal.
This portage has new wheels, and the sakae triple crankset has been replaced with a cheaper old double.
Looks like this bike was raided for its wheels and crankset (not sure about the FD and RD. I can check mine) and later rebuilt.
Are the new wheels a net plus to the value? Up to you.
I would buy it if I needed a touring bike and consider it a pretty good deal, despite it needing a triple.
No bike I have ever ridden a smoothly as my Alyeska in terms of long distance straight down the road riding. Not even my Trek 620. Have gone on loaded tours with it and the geo is excellent. DT shifters aren't always my favorite, but they work better than bar ends for halfstep+granny gearing.
The 650b models are considered the rarer more valuable models than the 27" versions.
My vote? Get it right away, maybe ask for a bit of a discount b/c of the crankset.
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The bicycle, the bicycle surely, should always be the vehicle of novelists and poets. Christopher Morley