the stock speakers are 1 ohm. if you don't want to update the speakers, then you are pretty much stuck with stock. if you can't find one, they are expensive af ($168 for just one speaker, without the tweeter).
the route i took was to replace both front speakers and the amp. i constructed my own harness so that i could wire it up without having to cut the stock harness. used focal 6.5 speakers with separate tweeters to maintain the stock look. unfortunately, i had to destroy the stock tweeters to use the 'baskets' so that i could mount the new tweeters in the gauge holes (stock location). using a kenwood marine amp, 4 channel, bridged into 2 for 300 watts (kac-m3004 shows msrp at $200 but i found it for about half of that). later, i will 'unbridge' the amp to run it as a 4 channel, and mount another set of speakers in the fairing lowers.
the biggest downside to this is that now i don't hear the saddlebag speakers. they never were very noticeable, but now even less so. i eventually plan on replacing the rear amp with another small class d amp, and the saddlebag speakers with something else. but i'm in no hurry to do so.