Okay, so considering this item used to be so rare, there are hardly any trades to find currently about the value of it, but what I do know, is that it's definitely going to go down in price.

The reason for this being that the vita-saw was only available in the uncraftable version through spending 20 dollars in the mann.co store.

Right now, with the meet your match update, we are able to buy the class bundles with uncraftable versions of every weapon that class has that isn't a reskin, and this includes the vita-saw. As they're now going to flood the market due to new or even experienced players buying the bundles of weapons, especially considering the medic bundle is extremely cheap, they are sure to lower in price. You can already see the new classifieds coming in with uncraftable vita-saws after buying the bundle. If this price is kept, it's possible to profit purely by buying the bundle, waiting a week and selling the uncraftable vita-saw.

Now, I have no actual clue what a price for it should be, and therefore I'm leaving a very wide range so that someone else with more experience can make a submission for a better price. It'll slowly drop in price, nonetheless.

EDIT: Here's a link to the price of the bundle. https://wiki.teamfortress.com/wiki/Bundles#Starter_packs

You could buy this, wait a week, sell the vita-saw and name-tag, and make a massive profit. This is why I believe the price should change.

This is my first suggestion, so please try to leave constructive criticism instead of insults.