Depending on cosmetics and condition...
The '66 should bring $800 easy enough. The .38 caliber is very desirable in the Cowboy Action game and the SS kit currently goes for about $175 by itself. Whisper Springs or SliXprings would help boost the resale price a few bucks too. Short Rifles and Carbines tend to be more desirable, but a few folks prefer the longer barrels of the Sporting Rifles.
Six months ago, I paid $625 for a lightly engraved used 20" Uberti .38-40 1866 carbine with 3rd gen SS kit, coil spring conversion kit, Grabber front sight, spring kit, and ladle reinforcement mod, but that was an exceptional deal.
The SASS Vaqueros should bring around $1000 for the pair - there was a pair on the SASS wire classifieds a few days ago for $1100, but it looks like a deal was struck for something less than that.
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The Polytech 1897, around $350 or so.
Check Mernickle's Web site for current prices on the leather and price them accordingly, as per wear, etc. If they are double side rigs and you're a big boy, I might be interested - I'm 6'4"/320 and take about a 44-46" belt.