Striker Header/Coolant Tank Recommendations

[philfingers]

Well I've been working on the Striker that I bought off Pete to sell on.
The new owner came to collect yesterday and drive it home to Sheffield. He called me to say it had quit about 10 miles up the road and the sage unfolds. Will start and run fine from cold, gets hot and stops, until it cools for 10 mins or so and then will run again till it gets hot.
Anyway, it appears it could be down to tight valve clearances. It's run on the drive today for 30 mins, fan had cut in and then the coolant tank burst. I suppose looking on the bright side it kept running and did stop when it got hot.
So now need a new coolant tank. Any suggestions, the one that's in there was a MkIV Escort I think. What are folk using now? I used a Clio/Kangoo one on my old Striker and Phoenix, but on this car the battery would need moving, more work I could do without!
Any suggestions welcome. Few pics attached, I was trying to figure out the cam, which Pete believed to be a 244 Kent. Lift doesn't appear to fully agree with this 10.16mm on IL and 11.01mm on EX. That's maybe not really accurate as the DTI may not have been totally straight

[philfingers]

Pretty sure it's cured. I think a combination of valve clearances slightly tight and more importantly due to the layout of the cooling system in the car where the pressurised [MkIV Escort] expansion tank is lower than the XR2 MkI header on the crossflow head. An air lock had developed in the top of the head, so it was running hot anyway, compounded with the out of adjustment valves and when hot the valves were slightly open and it wouldn't run.
Had it running for 30mins last night, with the bonnet on and water temp didn't go over 92-94degC and fan was cutting in and out as required. Only stopped the once as the tickover slowed due to under bonnet temperatures, but restarted fine and upper tickover to about 850rpm
Thought I post the findings for everyone's info,
Phil