Cal 29 mast
You may be able to simply replace your spreaders with aluminum ones and maybe even change your masthead fittings, and then re-rig with internal halyards. See if there are any labels etc on the mast that identify the sparmaker. If so, it will be useful when communicating with the folks whose links I've included here. If there is no i.d. available, you may be able to match up your spars with currently available ones by matching up measurements and profiles with drawings (see below).The mast, boom, and fittings on my 1976 Cal 2-29 were replaced with Isomat equipment. Good stuff, but out of business. EB Spars in Quebec has an inventory of Isomat parts. www.ebspars.com, or call Jim Kulibert at 704-597-1502, in Charleston , SCIf your rig is original, it is more likely to resemble closely spars made by Dwyer or Kenyon. Kenyon, too, is out of business, but parts and spars were bought up by Rigrite:www.rigrite.comDwyer is (imagine this!) still in business and have a wide variety of spar sizes and profiles. They will send you information sheets and a catalog with detailed drawings and dimensions that will help you match what they have with what you have. Good chance of a match. This link is your best bet so I've inserted an active link below.Rigrite also handles Dwyer products. Nice helpful folks, too. They have an extensive line of other rigging stuff. Consider building your own mast. It's not impossibly difficult using extrusions and fittings from Dwyer and outfits like Rigrite. FredT