Amazon's orders are 'fulfilled' by various other companies and some offer postage to Sri Lanka, but it's only through Express/insured so it's expensive. Register with Aramex if you're keen on buying stuff online (especially items located in the US).
It's sad to see a respected name slapped on some TATA-inspired trash that's made in India. They could've named it DATBUN for all we care! (Gibson-Givson, etc... It's an Indian thing )
The carb cleaners on their own aren't that great, to be honest. Your best bet is to get a mechanic to remove the carb from the manifold and clean it thoroughly, then spray the carb cleaner and get a good engine tuneup done to top it all off.
The door cards are nothing more than a sort of chip-board. I've seen people make new ones by using the old ones as a template and then draping it with a vinyl material of their choice. If I can dig up those threads I'll post them here. (supposing your original cards are still present) The only downside to making new ones is you'll lose the detailing trims and whatnot on the original. It'll just be smooth. Please post some photos!
Welcome! Black rear bumper with a chrome front bumper will look bad, so why not explore Panchi for a replacement? If one can't be found, then you would have to go ahead with the black rear bumper.