How do I defeat Indonesia as Portugal?

I'm in the 16th century as Portugal, I have a good income from colonial trade by this point and a big enough regular land army for my purposes (6.4k troops drilled to 50%). But my navy sucks (20 ships, only 4 heavy ships, waiing for reformation era tech).

So I go against history and try to defeat one of the Indonesian kingdoms from my colony in Australia. And WTF they have 180 ships and 74 of them are heavy fighting ships with stats like the early galleon apparently. They ate my navy for breakfast. That would probably crush most naval powers in Europe as well.

So at this point, to match their naval power, I'd need 80+ heavy ships, which would amount to more than 10k ducats (forgot the price of those heavy ships, could be higher). Technically doable but it seems like a huge waste at this point, I'm not sure if there's a big number of smaller ships I can build to kil all the heavy ones.

I'm thinking of delaying investing in the navy until I unlock better tech or should I do it now? Maybe for fighting the Indonesian kingdom allying their neighbor and asking them for food and military access would be a workaround for this?