Thank you for your words of appreciation. I am, like all other pakwheelers, in awe of your immense depth of knowledge.
A point to note is that I am based in Islamabad/Rawalpindi where I do not have the old shops and scrapyards at my disposal as opposed to Karachi. With reference to getting a core built here locally, here are my thoughts on the subject:
1) The only company (to my knowledge) that builds radiators from scratch is the old Allwin Radiators based in Karachi. I contacted them. They arranged to see the radiator and declined to supply me with one saying that they (a) only do aluminium radiators and (b) they do not have the dies to make a 2-1/8" thick core. Plus what they make are fin and tube radiators as seen in the pictures below:
Fin & Tube fitted to today's cars
Cellular Film - what is fitted to this car
2) Other places take an old/used larger radiator and cut it to the size required. So I end up replacing an old core with another old core. Who can tell how much life is left in the used radiator I would have ended up with. IMHO Russian roulette!
If you know of a outfit in any part of Pakistan that makes cellular film radiators from scratch, I'd will love to hear about them. The core I have fitted was made in the UK for me to my required size. It is brand new and hopefully out last me .
On the subject of coolants, you are absolutely right. I cannot find old school green coolant suitable for this car. Everyone sells OAT stuff. Osaka coolants out of Karachi make green stuff but I think it is just coloured water. However, I have been in touch with Liqui Molly in Germany. They make RAF 11 and RAF 12 coolants. The RAF 12 is OAT but the RAF 11 not OAT. My guess is that it is HOAT. Anyway, emails were exchanged and I am informed that RAF 11 is perfectly safe to use with copper/brass/solder radiators which is what I have used 50/50 mixture. The coolant you have suggested is not available in my cities.
The water pump has a mechanical seal affair as seen in industrial pumps where the gland packing goes. There is a carbon ring running on a hard steel face. I don't think it requires any sort of lubricant. Plus I have a spare seal with me so not to worried about adding any seal lubricant to the system