There should be no issue buying solar panels from overseas. But then how many are you buying? The weight and cost would probably trigger kastam first before SIRIM comes on. Then there are batteries. No way you could get them shipped easily.

The best option is buying local. There are from time to time we hear about some solar companies selling products or services in /K. But no one keeps track of these things. You just have to google through the pages to find them.