Notice:
The advice given on this site is based upon individual or quoted experience, yours may differ.
The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.
Good news is that the masts are interchangeable, sails and other rigging are not. If you are not planning on racing her, I'd search anywhere and everywhere for a mast in the 28-31 foot range and get the rigging made to fit.
There is also a number of guys that were parting out their old boats - you might have to dig a bit in the swap meet section to find it. They might have what you need.
Also Check - San Juan 24's, Catalina 27's (though I'm not sure on those), Coronado 25's they are all in the same neighborhood.
Welcome, Edgar... I don't feel qualified to offer much advice on this issue, but I'll recommend that you post your question on the "Catalina 25 Specific" forum, which is where the right members will see it. As I understand it, the Catalina 27 has a different extrusion for the mast, and is therefore not interchangable with the 25 Standard Rig. I don't know what else might be... You can always contact Catalina Yachts to learn the source, in case you end up needing to buy new.
Notice: The advice given on this site is based upon individual or quoted experience, yours may differ. The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.