CPU compatibility for power mac g4 digital audio

Hello, this is my first post...
i received a mac g4 digital audio 733mhz and i would like to go dual, but i have limited budget...so i thougt i coud buy a second hand dual cpu but i dont know which one???

can anyone help me?
i found some that were on a quicksilver, some that were on a mirrored drive...
which is one i can buy?

You can find out what will work with your system on

http://www.macsales.com/

If you cannot afford their prices you can always hunt around on ebay after you know what cards will work

there are a good vendor through

thank you!