Adam,
The bolt's functions are to prevent the track from moving forward and aft on the sail, and to prevent the slot of the track from flexing open when under load. You will need the bolt rope to carry the load. If you simply bolt a track to a sail (without a bolt rope), it will tear away the moment you put a load on it.
Using the seller's included piece of sail's "foot" as he has pictured, might work on your old sail, if there is enough surface area to sew it together, and not interfere with the "plate" if there is one (see Note). You should buy the track before I do, as they are rare, and it is a bargain.
Note: The more modern sails that EP built used a plate instead of a bolt rope. What the seller has might include the plate. The modern cloths (PE series) "wrapped" at the foot, and the plate was inserted (slid in from the leach side) and the bolts went through the track, cloth and plate, and the plate transferred the load to the sail.
Give me a moment and I will add a photo which will help illustrate much better than a thousand words. Either way, you will need to have a sail shop or other source, work on your sail.
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Philip
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