hello - sorry to be disappointing, but regret unable to help remotely with your glass.
I suppose that in some ways it does have a very tenuous resemblance to some of the C19 dumps, but my own opinion is that it wasn't made as such, and is probably a simple sculptural free form ornament. I doubt that even the largest of the period dumps exceeded c. 8" - 9" in height.
I don't recall seeing this shape before, and in the absence of a label or backstamp then the only positive id is if someone else has knowledge of its origin - so you may be a long time waiting. I'd imagine it was made some time in the last 10 - 12 years, unless you have acres of wear on the base, but can't see this from your pix.
Values are not something discussed on this forum - far too subjective - and what may be worth many shekels to one person may be of no interest to others - you can of course trawl the internet sales sites or past auction sales records and this might provide an idea - that's if you can find another example.
Glad to hear that this is a very interesting piece for you - that's the best way to buy

Fingers crossed someone may be able to help.