Hey James!
I would hazard on opinion of $20 - $40 for the vise as shown. The things that tend to hold a price down are rarity, condition, usefullness and the ever present "OMG....have to have one" fad.
Rarity - Littlestown vises were very popular and they aren't hard to find, they are a great home vise and they sold a ton of them for years judging by how many seem to pop up for sale
Condition - freshening one up is mostly a matter of time and hand labor since for the most part they don't require exotic materials, expensive machining, or intensive parts searches for that New Old Stock trim piece. So a person can buy one in unkempt shape (as long as it isn't cracked or missing jaw faces, etc)....derust it...wire wheel it....fix whatever needs fixing (lead screw collar, hold down nut/bolt, smooth out gouges..etc), then paint it and assemble. That is one of the best things about vises....you put your labor and ideas into something with maybe 9 parts and you get a product that looks great and works as intended 50 years before you were born and nothing modern works any better
Usefullness - check out a Columbian Gyro Vise....its rare...its got "wow" factor...but it isn't really more useful than a simple vise....Your Littlestown vise is very useful and would work great in any home or hobby shop....bigger vises have a bit more usefullness since they can work in a business shop environment/home shop also...then you get to the Big Vises and even though they are limited by usefullness (most of us can't even mount up a 150 pound Reed on our bench) they have the above Rarity
OMG factor - some vises just have that certain Wow factor....maybe the maker was known for making other high end items.....sometimes they are just doggone "cute" (think of the Baby Wiltons...LOL).....some vises are just eye candy and folks will pay quite a bit just because of that Wow factor
All of the above is to just let you know that you may or may not be able to sell a vise for what you think that it's worth to you. James, you have done some fabulous work on your vises and they are a testimony to your good work ethic. Keep up the restoring and showing us your efforts and don't let a sell price bother you.
Craig