Hi Max
My first suggestion would be the Naish Nalu 11'4 (wood version is the only one in this range with windsurf base attachment). This is an AMAZING all round board! great for fun windsurfing, glides very well in flat water for simple cruising and surfs incredibly well! It is the board for all seasons in my experience...given its weight and construction i would actually rate it to be very durable.
i have 2 SUP fishes on the South Coast Victoria region (one second hand, one brand new) they are 9'6 and have mast track. Many of the local crew have been working on the concept with ourselves and Stonker to develop a light wind, wave sailing SUP that was great to surf when SUPing and Great to grovel onto waves in windsurfing mode. This board has been incredibly impressive and we are 'stoked' with how it sails/wave rides. It is a thruster set up (no foot straps) and the closest thing to it in the Naish Range is the 9'6 Hokua (unfortunately the Hokua does not come with windsurfing adaptability). The board is also a very buoyant cruising board but not a flat water speedster as has increased rocker for surfing (more volume than the Hokua) and i am 84kg. the board is glass so prone to paddle dings down the rails and you would not want to slam the rig down onto the nose too often but there are many of us riding them on the Victorian Surf Coast as pure SUP's and Windsurfers with large grins. The dings are superficial and this type of construction is easily repaired if your were to smack the nose off it. I would highly recommend any similar boards..the Naish for cruising and the fish type if you are keen to execute tight turns. There are several manufacturers of similar concepts around Australia. Airwave are making a super light version of this type of short board / Fish SUP that can have a windsurf track added for custom orders.
happy hunting
Nick