I did a little looking on the internet to see what was available.
The 5-car Concor-Rivarossi set which is not available from Concor according to the manufacturer’s website, IS Available on an auction site. Latest bid is $25 + shipping.
http://i10.ebayimg.com/03/i/02/4a/b3/2d_1_b.JPG
This is the set that includes baggage-dorm, 2 sleeping cars, dome car, and sleeper-observation.
The Rivarossi (old Atlas) sleeper-observation is also available by itself on an auction site. However, it is lettered for PennCentral.
http://i8.ebayimg.com/03/i/02/50/de/34_1.JPG
Walthers also lists the “shorty” Arnold observation car available ONLY in Souther Pacific colors, and says is being discontinued. Your hobby dealer may be able to order it. Would have to be repainted.
That same car IN SANTA FE is on auction site for $2.26 but there have been 4 bids and may be more as deadline nears.
http://www.transactual.com/pix/aug0179.JPG
The Model Power observation is also available. Your dealer can get it from Walthers.
http://www.walthers.com/exec/productinfo/490-3042
Why oh why is window panel painted a color instead of being left stainless steel. To use this car, you would want to disassemble, remove plastic “glass” window insert, remove paint as much as possible, paint with silver or aluminum. Decal for the Santa Fe name you lost when correcting the @#$%^&* colored window panels.
I believe it is trains.com’s policy not to encourage forum user’s to specifically link to particular auction sites here, might be subject to commercial abuse. If you cannot find it by guessing, email me. My address is “leighant” (without the quotation marks) followed by the “at” sign (@) and “hotmail.com”. (By not writing it exactly as you have to type it, it is less likely to be picked up by a robot program gathering e-mail addresses to send spam. But I assume you are a real person.