dwyer aluminum mast has many different extrusions to choose from I found them on the internet by searching for sailboat mast spars. You can find alot of this info on Google.com. They also have reasonable prices. Happy sailing.
While I no longer have a C-22, I had replaced my mast with a Kenyon spar that had a similar extrusion shape. I reused my mast head fitting into the kenyon spar and cut the spar to length. You may consider this if you can locate a salvage yard, as I did, Don''s Salvage in Largo,Fla.
Otherwise try the Catalina Owner''s website ads or "Catalina Direct", their parts source.call them at 916.843.1971 they can send you a catalogue of OEM or improved parts. These are from the new updated 2002 cat.
#D1209 is 25'' mast complete @ $870.-1980-85
#D1212 is 24''-9" mast extrusion $383.-1986
#D1211 is 25'' mast extrusion @ $383.-1980-85
#D1220 is Boom complete w/Goosenk @ $223.
good luck, Mark