I am wondering if an Arctic Cat Bearcat with the 20" wide track may meet your needs... lots of flotation, you won't be making any highmarks, but with that wide of a track, in the right snow they may go anywhere. The Bearcat is used a lot in Alaska for movement of people and supplies, it may work pretty well for you too!
Spring has definitely come to the West coast, it's supposed to be 75 tomorrow. I'm still looking to get out at least ONE more time on the sled

I love sledding in a T-shirt!

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2007 RMK 700 155", 2008 RMK 600 155", 2006 RMK 600 144", 98 Indy 440, 95 Prowler 550 2-up, 1990 Indy 650
RIP, destroyed by fire 1-22-2008

04 RMK 800, 05 RMK 600, 02 RMK 800, 97 RMK 700
http://www.avalanche.org/accidents.php