Can anyone identify this i think it's an alpha but i can't tell for sure and the owner has no idea at all if it's a bravo i was going to buy for a spare

That is a pre alpha, called a #1, probably pre 1978 by the looks of it

ok thank u very much for the info it is too far of a drive to go look at so not going to buy this one

identifiers of the early merc drives....serial numbers depict which specific generation of drive
https://bpi.ebasicpower.com/faq/mercdrives.htm

Its called a MC-1 It is a precursor to the Alpha drive.

Thank u all very much for the info

They tab with the hole on the top is the giveaway.

now I know I'm a newbie kind of learning as I go thank u I will keep my eye out u guys saved me a wasted trip i was going to drive to look at it