For MGA the BMC part number is 88G320
    (previously BMC part no. ATA7047)
1-1/2" ID x 2-1/2" OD x 3/8" Thick.

Alternate part numbers:
88G320           BMC, Leyland, Rover
ATA7047          BMC alternate numbers
G444, 2794,      BMC alternate numbers
3H2835, 544100,  BMC alternate numbers
88G490, A1492    BMC alternate numbers
GBS192           A.H. Spares
88G320 		 Brown & Gammons
120-800          Moss Motors US
5-885            Victoria British

MANUFACTURER     PART NUMBER
DDS (single lip) IN38.163.59.52SC -(w=3/8")
DDS (dual lip)   IN38.163.59.52TC -(w=3/8")
Federal Mogul    51098 -(0.437" w)
Global (single)  OS1.500-2.500-.375SC -(w=3/8")
Global (dual)    OS1.500-2.500-.375TC -(w=3/8")
National         51098 -(1-1/2" shaft, 2.506" OD, 0.437" width)
National         710414 -(0.375" w)
                  --sometimes incorrectly shown w/outer flange
SKF              546118 -(2.505-OD, 3/8-W Teflon/PTFE Lip Code: T)
Timken           51098 -(1-1/2" shaft, 2.506" OD, 0.437" width)
Timken           710414 -(0.375" w)
                  --sometimes incorrectly shown w/outer flange
TRW              51098 -(0.437" w)
Walker           51098 -(0.437" w)

Timken           450067 - (1.500x2.506x.0500w for 2.502 Hsg, Nitrile)
Timken           21702-0655 -(type 62 - PTFE Lip) -(w=1/2")
Garlock          217020655 - (type 62 - PTFE Lip) -(w=1/2")

Cross-listed part 450067 manufactured by Timken, Duralast, or Acdelco - providing compatible interchange with the Timken and Garlock 217020655 -(w=1/2").

51098 seal may seem tight in the housing, but it works when driven into place.

Applications:
MG, MGA, TD, TF, all;
MG, MGB, 1962-1967 w/Banjo Type Axle;
MG Magnette 1953-1968;
MG Midget all, 1961-1979;
Austin A55 Mk 2 & A60;
Austin Healey 100, 100-6, 3000 BN1-BN4 w/Early Spiral Bevel Diff.;
Austin Healey Sprite MkI, II, III, IV, 1958-1971;
AH Sprite & MG Midget (differential housing "C");
Morris Minor 1000, 1956-1971 from (c)228267 to (c)990289;
Morris Oxford Series 5 & Series 6;
Riley 4/68 & 4/72;
Wolseley 15/60 & 16/60;



710414 seal is shown here with the extended flat face flange. There may have been a change of design or reallocation of part numbers making this one appear on the market in two different physical configurations.

99150 - Speedi-Sleeve for differential front seal