Crate Motor Part Number Help

[PHOENIX]

I have a crate motor about 5-6 years old. Its the $1300 Goodwrench 350.
When I called around for a damper they of course asked the year and model, etc. When I told the guy it had the crate motor he wanted to know the number of the motor. I didnt know this. I told him the crate motor and price and thought he could go from there. He brought up a different damper for the crate then the stock 305, the stock 350. He told me the newer crate motors have some different (improved) parts.

I think I need a couple new valve stem seals and want to know if they are the same on these crate motors as they are on the original motor.
Anyone know?
Also what other differences might there be from the crate to original?
Anyone else ran across differences when buying parts from the dealer?

Please see my other thread about oil in cylinder.

Thanks!