Watch out for Polish post-war reworks and/or Polish made fake SVT bayonets, based on some parts from original SVT bayonets. What this site sells as SVT-38 bayonet is not authentic bayonet, but also a Polish "rework". What they have as "non-refurbished" bayonet has very funky markings. Buyer's beware of unscrupulous dealers.
For $220-250 one can buy authentic refurbished bayonet, they pop up on EE from time to time.
If you read the text on his listing for the "SVT-38" bayonet, he makes clear that it's a post war Polish refurb. But they aren't as rare as he's claiming.
Corwin Arms brought in a number of them last year, and was selling them in and around the $150 mark (and he was clear about what they were). Nazi Bill at Things Military is just up to his usual shenanigans, keeping enough truth in his ad copy to avoid being called out on mis-representation, then charging the moon for something that's not actually all that rare.
Looking at that Bayo, I'm pretty sure it's one of the ones that Corwin-Arms brought in last year, and then through whatever process of intermediaries, has ended up at Things Military. I wouldn't be surprised if the other SVT bayos he has listed also originally came in from Corwin-Arms - which means they were all Polish refurbs, as that was the last (as far as I know) significant batch of SVT bayos that came into the country.
Martin from Cowin-Arms was very clear about what he was selling, so might as well pass along the details (because this is probably what you're actually getting from Things Military):
After the war, Poland maintained the SVT-40 in their arsenals well into the 60's, and possibly early 70's. They were primarily used at military colleges for training and drill purposes. These were refurbed through the Polish Arsenals (not sure which factories), and represent a fair number of the SVT's that have ended up in Canada over the past couple of years as they've finally been released onto the surplus market.
As a drill/training rifle, the Poles needed bayonets for them. These were in short supply from the Soviets, as they were more likely to be lost/destroyed during the war than the rifles themselves, and a great many were melted down by the Soviet arsenals after the war.
The Poles took the expedient of getting as many bayos as they could from the Soviet arsenals, as well as partials and parts and incomplete stampings. These were all sent to the Wilkas / Wikolak knife manufacture to be mixmastered together, and if necessary completed.
Wilkas /Wikolak is a fairly decent knife manufacturing concern, and even makes AR-15 contract bayonets to this day.
While these SVT bayos aren't what I would call "pure" - they aren't fakes or repros either. They were genuine East Block manufacture as a part of the arsenal system from the time (50's and 60's refurb).
I have one "pure" bayonet I got from a different dealer a while back (not for sale at any price) and one of the Polish refurbs. Generally, if you look closely at the wood on the handles of the Polish refurbs, you should be able to make out a faint stamping of the Polish Eagle crest. I have some pics I'll look up when I get home tonight if I remember.
Anyway.
Value? Who the hell knows. Whatever someone is willing to pay for them. As a general rule though, I don't deal with Things Military. That place has gotten up to some shenanigans in the past, and he's done a few things to give the Canadian firearms community a bad name over the years.