You need to look at other brands as well since Kubota really got stuck behind everyone else in the USA, specially when it comes to geared transmissions, as they had to follow the trend of the HST. Interestingly enough, they do offer a 16x16 transmission with dry clutch in Europe starting on the L2372 model (equivalent to the L3560).
As far as costs between hydraulic shuttle or dry clutch. Back in 2018, when I happened to check some prices, Kioti had the DK5020 Hydraulic shuttle and 16x16 transmission selling for €19,500, which is inline with other brands offering the same 16x16 but with dry clutch like the Branson 5025R or LS R50. So I don't think that there is an huge difference between dry clutch and hydraulic shuttle. Definitely won't get near the HST prices.