However a new mast, boom rigging and sails will cost far more than the boat will ever be worth. An old boat like that is essentially worthless without those key items.
I guess you would like to keep it compliant with Hurley specs but this will be expensive. As said crazy compared to value of boat. However a boat of that size could go nicely on almost any mast of comensurate size likewise boom and sail. So look for dinghy mast/rigs and sails. Any piece of tubing can be used for boom. Mine is a section of carbon fibre tube (a broken dinghy mast). The actual size of a rig ie mast height etc is a function of compromise. A large rig will go better in very light winds but be a devil when when increases. A smaller rig will give comfortable sailing in stronger winds. My preference being for latter.
So any mast from 20ft to perhaps 24ft of reasonable strength will do. Some dinghy masts might be too light in thickness. Your Hurley will be a lot stiffer (resistance to leaning over) so needs perhaps more robust mast than some dinghies. Then you need spreaders if mast is not short and stay wires. You would do well cost wise to buy dyneema (spectra) 5mm and make up stays. You need a base arrangement that will enable you to tilt the mast back for raising and lowering. A gooseneck can be fabricated from scrap SS metal.
So just start with what you can find and we will help you from there. Or just use it as a motor boat. ol'will
Thanks for the feedback. I am quite handy and so, making a boom sounds straight forward enough. I have all the old stay wires that will need remaking with new SS cables and two spreader tubes attached to two cables. It sound like I am best searching for a mast first from boat salvage or sales adverts. Hurley owners website looks like the mast size on this boat was 24 foot going by the specs, but I will keep a lookout something similar.