You can order a new custom trailer from boatmate, phoenix, eagle, or others. It is usually cheaper to get one from a trailer manufacturer in your area. Many will only sell through a local boat dealer, so you might want to call local dealers. They will need to custom fit the bunk supports to your boat make, year, and hull. They will either already know the hull shape and dimensions, or need to measure your hull specifically. At a slightly lower cost is to a new trailer with bolted adjustable bunks. Load rite is probably the most common brand for these and makes a pretty nice alumimun trailer with bolted adjustable bunks. Load rite also offers and inboard ski specific trailer with a dropped rear cross member as a prop guard for inboard boats.
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