I had one that I sent to Whetstone to convert to 3-piece a few years ago. Don't remember the cost, but they did a great job. Not sure if they are still in business, though.
I don't think most places can make a 4-piece, though, so if you want that, you need to buy one. I had an Aquabound and it's been fine for the few times I've loaned it out mid-river.
Join up, suckas.
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