you can look at Rune trader in any major cities rune prices, you can salvage runes off with expert salvage kit and also sell them to rune trader then, its usually not worth the trouble trying find person to buy runes, with only exceptions rly high end (10k+) runes like sup vigors.
When ure trying find price for rune, look between sell & buy from rune trader and somewhere in that area 
In presearing there arent rune traders and market is different.
Runes
-50hp Major runes, all versions
Superior runes with Minor rune icon
Superior runes with Blue color
Superior or Major runeswhich remain unsalvaged on a Blue armor/garb item
These are referring to runes that no longer drop or are available in the game.
Before they were updated Runes dropped differently, in general terms they would only be indicated by their text not by their colour/rarity.
The existing items were not removed when the change was introduced so there are still some of the old stored on accounts and therefore fall into the 'Pre-Nerf' list of items.
They sometimes crop up on Xunlai Sell threads, there is a pre-Nerf rune in this thread.
Unless you see one up for sale or have an old account you won't find one now. They are only useful for collectors that might want a piece of 'history' as they have the same function when used.
Anything mentioned in the pre-Nerf context no longer drops in the game (they've been "Nerfed") so you'll only see them from other players.
you dont need to destroy armor piece,just get a perf salv kit,it has 100% chance of NOT destroying.
or take screenies and post them here on the armor with the runes you are thinking are pre nerf runes.
I agree with OS T, if you provide screenshot of both the Armor Inventory Icon and it's description (you can do this without removing the rune from the armor), we can tell you if they are prenerf.
A few rules of thumb.
For the most part, but not limited to, Prenerf runes will have a different color/rarity and icon picture than they do today.
Here is one of mine, even though the +50HP itself still exists, this one is blue with the Common Rune Icon.
There are also some prenerf runes where the functionality or benefit of the rune/insignia no longer exists.
In all of these cases, if you do post them here for informational, fair warning that you may get offline offers for them that may or may not be low offers. Be aware these can be pretty valuable, however also takes a specific audience to be interested in them. If you post here and get confirmation if any are prenerf, you can then post in Price Check to get some input on them before you put them up for sale.
Sorry, I probably should've provided this tip in my prior response. What you would need to do is for any that are +x with Health-xx, or +41 or +50, use a Perfect/Superior/or Export Salvage kit just to get the following screen, you won't have to actually merch it, just to see the actual rune. If any that are +3 and not gold, or +2 that are not Purple, are Prenerf. So basically if this screen shows that the rarity of the rune is not what it is today, it is prenerf. (This is example is not prenerf, just showing how you can see the rune without removing it)
Others may have more input on the topic.
