Quite a lot. Ive never been in the market for a tree that valuable to give an accurate estimate. I have seen some pretty hideous material over 40 years old go for $600+ So my uneducated guess would be somewhere between $1000 and $3000 dollars considering the lovely shape and deadwood.
If that is your tree it could definitely use some restoration.
Clean out the dead needles, prune it, re wire it, clean up the dead wood with some carving and lime sulfur, and restore the live vein to a nice reddish hue. I would also try to get it into a nice unglazed tokoname pot, and do a top notch moss job on the base. If all of this is done properly who knows how much you could sell it for!
The following user(s) said Thank You: Youri1995, le_beetle
This is nice material. However, currently I would consider it as untamed stock. You would have to (have it) cleaned up and styled in order to get the best price for it. In the hands of the master this could be a succesfull tree, imho. However, without the styling (And without knowing the actual size) I would not say thousands of dollars. On ebay you would grab a few hundred dollars. In the right hands, after styling & through a recognized seller it may top 1-2000.
i agee jelle 300$ would be the max ...the trunk has no taper, there looks to be no obvious nabari formed, the branches start too high on the trunk.the foliage pads tho look to have been shaped at one time are very neglected and brsnch structure is too compact for its size. in short its quite a mess. seeing it is a juniper i think an airlayering of the trunk would be an option to shorten it and restyling can begin