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Assuming it is 1"x1" that is pretty close to the Lewmar Beam Track 0 (24.7mm x 24mm). The current size 0 has a max span of 400mm (15.8 inches). Since I highly doubt that the track design has gotten weaker, no i don't think this will work.

I would also point out that the size 0 on an end boom sheet is pretty marginal for your boat. I would really recommend you go up a size, which would not only be better for the loads but also allow you to span this distance easily.

If you choose not to go up a size then you need to build a support brace strong enough to carry the loads. If you go this route then the easiest base is a 1.5"x1.5" heavy walled aluminium square extrusion as the bridge and then custom fit wood pads as the seat braces

 

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The seats are highly unlikely to be in a plane parallel to the traveler. If they are, then no wooden blocks needed. But otherwise that's pretty much it.

I appreciate you got a good deal on the traveler, but it really is right at the cusp (when new) of what the current generation of gear could handle. I don't have the specs available for the older generation, but it is very possible if it isn't a modern style ball bearing race that it will deform the track itself from the sheet load.

 

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Ya, that is a much larger beast than you had indicated. It will be fine.

The downside is that it's a roller car instead of a ball bearing car. Nothing wrong with it functionally but they are not as smooth or as easy to adjust as a ball bearing track.

 

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Alex,

I agree wi you, but this one is so up sized compared to the boat the loads relative to design specs should make it pretty reasonable so long as the track isn't already dented from its last home.