You could put a new ring gear on the a12 one you have. Notch the old one, chisel it off and use an oxy torch (or a friends) to heat the new one and drop it on. Relatively easy job if you have heat.

ok thanks for the replys

get another a12 one and turf the 2 you have

should be three dowels definitely, no need for a heavy van flywheel on your motor

are you able to remove the ring gear off the flywheels and replace the a12 one with the a15 one.
might be cheaper/easier than getting the a15 flywheel lightened.

hey guys, can i pick your brains?... rebuilding my 73' 1200 wagon with an A15 i got from a vanette. went to use the lighter flywheel from the original A12 but found it has stripped teeth, so, got the A15 flywheel and have found that it has only 2 locating dowels for the clutch?... shouldnt it have 3?, could one have broken off?... there is a mark where the 3rd dowel should be but its not there and dosnt look like its broken off?... any thoughts?...
And should i get the A15 flywheel lightened or keep it as is?... i will be running 70degree cam with a 32/36 weber.
thanks...