How much are bobshirts worth?

There's something fishy about the street price of bobshirts. How much are they worth street price? Clarification would be greatly appreciated!

 

They're a rare reward from low lvl treasure trails.

They are a collectors item, and so their value is a little higher than it maybe should be.

 

Yes i knew all of that, was wondering a value (in RSGP)

 

I have no idea how much they are but i have a set which i never sold since they were realesed

back then they were too common =/