Need parts help

I have a 2000 model 4.3 V-6,outdrive ser.# OL42454,could someone tell me please If this is an alpha 1 gen 2,would like to order seasonal replace parts for this upcoming boating season(bellows kit,water pump,etc),also are the sierra replacement parts equivalent to mercury parts.Thanks,any and all help would be greatly appreciated.

Alpha I Gen II started in 1991 so everything after 1991 is a GEN II

NO Sierra parts are not equivalent........in some case they are a affordable replacement such as gaskets but specific parts such as gears and other things are best to be OEM (merc)

Some simple preventative parts can be used BUT most who have worked in the business would say use only MERC parts........(bellows water pump etc)

Oil and oil filters, fuel filters gaskets and other NON marine specific parts can be from other manufactures......
I use Mobile 1 15-50 oil, NAPA gold filters (wix)
Any gaskets as long as they are low cost (except motor specific if need be)

It is your boat do your research and you decide...........

Thanks for the quick response,OEM parts it is.Happy boating