Would probably have to be a GR2 as a lot of the weapons tech on the GR4 was moved to the Typhoon, not sure about the targeting pod.
Also, as mentioned, the Tornado which the RAF used was closely aligned to the Saudi version which is still in use, I would imagine the Germans and Italians are still using GR1 or GR2 type aircraft, they dont like to pay for upgrades to meet changing technology.
Then you get into the NETMA/PANAVIA politics, I could imagine it being a bloody nightmare to get information.
Still want one in my Hangar though.