E_merlin is on the right path I think. DT shifters = a higher end bike, and from what I have seen in a year of looking hard at mixtes that turn up for sale on eBay, CL, or elsewhere, a very small percentage of mixtes are at that level. That is, for a given maker, the mixte frame was offered on the entry level bikes, which were the most popular, and also maybe on a mid level model, but in much smaller numbers.
But even a 'garden variety' mixte can be a perfectly good bike, depending on your use. My daughter's Miyata One Hundred from 1987 is a great little bike, and there are lots of other examples in the mixtie sticky here. In this market we see good quality mixtes from Shogun, Nishiki, Miyata, Fuji, Panasonic pretty regularly, priced from $100-200. Peugeots, Gitanes, and Motobecanes turn up pretty regularly as well, though that can get more complicated as far as parts and maintenance.
To Terraskye's question: a mixte is by definition going to be a bike for leisure riding rather than speed, and with the better ones, distance riding. Take a look at the Miyata catalogs (
www.miyatacatalogs.com) from the 80s to see what that company offered: mixtes came in the entry level 100 and 110 model, also in the 210/215, an entry-level touring rig with cantilever brakes, a 40-spoke rear wheel, fender and rack eyelets, etc. There were two higher touring models in the Miyata lineup but the 210/215 is nothing to sneeze at, especially as they are very rare. It seems to have disappeared from the Miyata lineup in 1988 or 89, along with all the entry level road bikes. As wrk101 notes, it was an awfully nice bike, probably as good as a production mixte gets.
(edit to remove even more redundancy/agreement with Thrifty Bill)
Which reminds me to send an email about the 215 that was for sale in the Chicago suburbs recently! I have reason to believe it didn't sell as the seller got greedy and now may be more flexible. But if I buy that one (for the wife), another bike will have to go, and worse yet I'll have to come up with a convincing argument for why this one is 'better.'
FWIW $200 sounds a bit high for a basic model like that Raleigh. If it's early Taiwan production it may be heavier and cruder than the 80s Japanese bikes, with knockoff components. But it sounds like there may not be that many options in Edmonton.
A bike in your own garage is worth two or three on CL in some distant city...or that people are yapping about on C&V!