$20-$50 and hang it on the wall.
or save your money and buy a decent modern board that you enjoy riding compared to that old beast.

Great in their day but not now.

^Yep keep truckin. Ive still got my '85 custom Cornish Wave/Slalom in superb condition. Good for artwork. Modern sails have different COE so dont really make for comfy sailing stance on the old boards. Ive tried. Still have the original sails. So a retro sail day is possible. That's where you notice how far sail design has come. Old sails are quite light. But lack the tunable range of the new gear. But still fun. Id think the dumping fee an ok price to pay.

I think you can determine the price of old boards by their width. 150mm x 2.1m fence palings sell for about $1.90. 100mm x 2.1 are worth about $1.30. So about $3.20 for 200mm cover. If the board is 60cm wide, it's probably worth about $9.60.

Yeah but Mikey at least take the decent straps and pads off. Plenty of times I'd love to be able to get decent factory pads for a repair

I have a HiTech with some tiger stripes colour scheme shaped in WA by Aidan Nicolson of Murray Smith/Bombora in around 1985 supposedly based on Craig Maisonville templates but there is some Mark Paul influence in it for sure since Aidan used to shape the Bomboras. 8'6" thruster with single flyer/ winger narrow square tail acquired for $30 including "sock cover".

Have a Tom Luedecke Designs full colour 9'1" slalom shaped and glassed by Strapper's Michael DeSciasio in mid 1980s acquired for $25 including CoL period cover..

Also have a near perfect full colour Delta Designs 8'6" inch single fin pintail glass waveboard ,Sails and Windsurfing model, with modern rocker and mast track location, acquired for $50 including Sails and Windsurfing period cover..

probably paid too much for them....but then they will look good hanging on the wall one day.