028AV conversion to 3/8, what sprocket PN?

[Ed in Maine]

My buddy has an older 028AV that he wants to buy a new bar and chain for. He'd like to just get a 3/8 chain and .050 bar, likely 18", since when he upgrades saws it will probably be 3/8 and the bar/chain will interchange onto the new saw. Sound like a good plan? What is the PN for the sprocket that he needs and is it easy for us to change? No special tools needed?
Thanks,
Ed

 

[HiOctane]

If you use Oregon with a rim ,you need # 29917X .No tools needed except a torx key.

 

[rahtreelimbs]

Stick with .325.............that saw is better that way!!!