Moss box O-ring help

Would anyone have the dimensions or standard O-ring sizes for the two sealing rings for the countershaft and reverse shaft on a Moss box? This is in a 1962 E Type, and I am hoping that someone in the XK section knows the answer?
Jaguar numbers are C4284 and C4285.
I’m thinking #208 and #209 in standard O-ring size?
Thank you in advance.
Mike

E-Type must be different. Our JH and JL gearboxes have only one felt washer in the rear extension, 1" ID x 1-1/4" OD, no other o-rings.
However, the part numbers you quote are found in the GB gearboxes as used in the Mark 1.