Hi guys, I am trying to get some new oil seals for my hot rod's gearbox, but I don't know the origin of the box, I have been told it's from a Sierra. No-one will supply me with the seals unless I quote the type! Maybe one of you clever guys could identify it for me from the numbers on it. They are as follows:

Large 'B' on side
83 ET7AO39 BA
71 WG-7006
83ET-7006 28+
G24525 LK82
Gearlever held in with 3 bolts

Thanks for any help.