The 27" iMac Pro Apple already priced and launched years ago...
This rumored new one would have a bigger screen, better CPU, better graphics, less (starter) RAM, less (starter) SSD, better thunderbolt ports and same 10Gb Ethernet.
You can do your own estimate of price.
Those recalling the classic (relative) value pricing of iMac 27" should keep in mind that Apple successfully removed the computer + keyboard + mouse from that package and sold the
same monitor for the old iMac 27" "starting at..." price. So adding a "whole computer" + keyboard + mouse only to that will have to go well north of what ASD costs.
I'd generally take the prior iMac Pro price and use Apple pricing for less SSD and RAM to get my working "starting at...". Add something for bigger screen + "inflation" + "supply chain" + <whatever else>. I'm not sure where some subtractions can be realized after a bit for less RAM and SSD: leave out the keyboard and mouse as add-on purchases?
My best guess: one edition using an M3 (not PRO or MAX) for a Marketing "starting at $3499" price. Nicely configured above bare bones RAM + "half speed" SSD is probably towards or at the pictured price depending on what nicely configured means to each buyer.
I'm picturing loaded M3 MAX iMac "bigger" up towards $8K-$10K or so. How do I get that? Max out a Mac Studio with M2 MAX to estimate Apple pricing for the computer ($5399) then add a few thousand for this bigger monitor + keyboard + mouse + "inflation" + "supply chain" + <whatever else>.
By the same Apple math, how low can we go? Barebones a Mac Mini PRO with 16GB RAM + 512GB SSD + Gigabit Ethernet ($1299) and then add a few thousand for this bigger monitor (obviously more than about $2K for 27" ASD) + keyboard + mouse + "inflation" + "supply chain" + <whatever else>. In that scenario, MAYBE a "starting at..." down to perhaps $2999 becomes a possibility. But my guess there is $3499. Resolve half speed SSD and double the ram for +$600. Keyboard + Mouse sold separately.
If Apple wants a <$3K price for Marketing spin, baseline Mini NOT PRO or MAX (8GB RAM + 256GB SSD + Gigabit Ethernet) at $599 + a few thousand for the bigger monitor probably can get an Apple "starting at..." to $2999. Resolve the half speed SSD and double the RAM for +$400. Keyboard + Mouse sold separately.