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Currently running a 90mm Thomson that I think is -10.
Looking for an 80mm or maybe a touch shorter with a bike more negative rise (That makes no sense!)
I like the look of these but they appear to be super spendy:

Any other suggestions?
Turn a rising stem the other way up
I've got an FSA K force the came stock on my Orbea. It's 70mm and - 12deg, might be worth looking for something like that? In fact I might have a ritchey wcs 90mm - 17deg knocking about spare in the garage if you're interested?
https://www.superstarcomponents.com/en/tower-17-degree-rise-stem.htm one of these might work, and half price if you can get enough other bits together