Alright so here is the update.
Radiator neck and cap werent holding pressure, so I went to Tariq Radiator on Tariq road. He checked the condition and suggested to change the radiator altogether as a repair would leak again in a matter of weeks. He gave me 2 options:
1) denso original japanese cultus used radiator in exchange for 6.5k
2) loads khyber used radiator in ezchange for 4.5k.
Since i wasnted to keep things in original setting, 1 was out of consideration.
Also, the loads one now has too many vatiations, loads fins but lical top and bottom etc.etc.
I went to plaza and was offered 3 different types of radiators in copper
1) UAE made dolphin radiator new for 13k
2) loads one (probably with loads fins and local top bottom for 11k
3) original complete loads for 16k with Loads symbol embossed on top.
The old one i sold to some guy in the market for 2700.
And purchased the original loads one after discussion with @brownrose.
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