Well it looks in v good nick to me, correct .321 mvmt (the newer post 1968 Speedys have the .861), pre-moon case back, 633 HELs, 1171 bracelet, applied logo.
Can't quite make out the ref no on the bridge, if you can cross-ref it on speedmaster-mission.net to ensure the mvmt matches the case back year (although it's impossible to be strictly accurate).
.321 Speedmasters were worn on the moon, if the price is right then why not get a bit of real watch history. These and the pre-moon .861s are going to rocket (pun intended) in value.