Ford had one that was five ft. long. It was perfect for my L245DT. Not sure of weight on that unit. With the number of BX24's and others that size out there must be something available. Probably pricey as well.
Kubota M108 FWA loader, 2014 Kubota M7060,Kubota MX 5100, Ford 1500, Kubota Bx25 , Kubota RTV900, Kubota ZD331 Zero turn mower.Kubota B1200 Grey to be restored.
I'm sure you could source a 48 or 52 inch machine, check out some of the European manufacturers like Caroni or Maschio. Once you go flail, you'll never go back...
I finally broke down and got the 60" mid mount. Lovin it so far, I just leave it on there. In heavy stuff, I mow with the mid mount and rear rotary at the same time.