Starting with the standard Sqn T-Shirts:

101 Sqn standard black (also available as a roll neck.

10 Sqn standard red.
Those were also available in other colours, but red for 10 and black for 101 Sqns could be worn with a flying suit.

101 Sqn Ltd Ed - Last of the Fast. From 2011.

101 Sqn Ltd Ed 50 Years of the VC10.

101 Sqn Al Udeid - "Do You Want Some"

And the back...

1312 Flt (Falklands) in green...

...and black.
Tonks