Looking for a bit of good advise please. I've just had my 1.6td JX engine pulled out of my van as I was looking to give it an overhaul. However, after having it removed by the mechanic, he called me round to take a look at some things

Firstly, the cylinder head is cracked between every valve. It's going away for testing over the weekend. I've been told this may be able to be repaired (welded) depending of how deep the cracks are. I remain to be dubious about this as I am a long, time served welder/fabricator and weld inspector of more than 12 years. I don't think I could ever be fully confident that a weld repair on such a thing as a cylinder head would ever be 100%. Whats you thinking on this.
Theres more issues as the oil was like treacle, leaky gaskets and seals and we have not even began to remove the pistons yet. I have every faith in my mechanic as I have know him and his work for a very long time.
I've already sent the turbo to Garrett to get overhauled, the fuel pump is being reconditioned and pressure tested, injectors are away for work and the gear box is being re-built. So....as you can tell, an alternative motor is out of the question. Also, I very much like the original 1.6 td motor.
My big question is now.....Do I purchase a newly re-manufactured (bare) JX engine or do I continue to strip, repair and overhaul the existing motor including the cylinder head.
Thanks in advance.
Chappers