Well the stamped tag is blurry, but seems to be missing a digit. I read the photo as PN 110182 whereas the SNL says its PN 1110182 (page 198). Its also for later trucks (engine SN 270-497131 frame number 394577)
While the SNL only shows one terminal stud, the TM9 does show all three (only one is used as a ground back to the coil - page 187 fig 74)
Get a better picture of the tag to verify the model number but other than that it looks like a good late sealed (aka dustproof) dist. Functionally it would not matter.
$199 might be a tad high.. you can get dist rebuilt back to new for a few bucks. None of the part are really hard to find I even found the dust proof parts... $8, its black,
http://www.mcdonaldcarb.com/product_p/abc186.htm ) Dist rebuild kits are not hard to find either.